Updating Algorithm list in pyqgis3?

Question

I am attempting to run a union operation in a standalone pyqgis script and I'm receiving this error: Algorithm qgis:union not found

The union operation fails with this code:

params = {
    'INPUT' : vlayer,
    'OVERLAY' : vlayer2,
    'OUTPUT' : r'd:\tmp\union-test.shp'
}

operation='native:union'

feedback = QgsProcessingFeedback()

res = processing.run(operation, params, feedback=feedback)

When I attempt to run Processing.updateAlgsList(), I receive this error:

'Processing' has no attribute 'updateAlgsList'

Is this function named something else in pyqgis3?

I am using OSGeo4W64 on windows and appending the python plugins path:
sys.path.append(r'C:\OSGeo4W64\apps\qgis\python\plugins')

gdal:aspect
gdal:assignprojection
gdal:buffervectors
gdal:buildvirtualraster
gdal:cliprasterbyextent
gdal:cliprasterbymasklayer
gdal:clipvectorbyextent
gdal:clipvectorbypolygon
gdal:colorrelief
gdal:contour
gdal:convertformat
gdal:dissolve
gdal:executesql
gdal:extractprojection
gdal:fillnodata
gdal:gdal2tiles
gdal:gdal2xyz
gdal:gdalinfo
gdal:gridaverage
gdal:griddatametrics
gdal:gridinversedistance
gdal:gridinversedistancenearestneighbor
gdal:gridlinear
gdal:gridnearestneighbor
gdal:hillshade
gdal:importvectorintopostgisdatabaseavailableconnections
gdal:importvectorintopostgisdatabasenewconnection
gdal:merge
gdal:nearblack
gdal:offsetcurve
gdal:ogrinfo
gdal:onesidebuffer
gdal:overviews
gdal:pcttorgb
gdal:pointsalonglines
gdal:polygonize
gdal:proximity
gdal:rastercalculator
gdal:rasterize
gdal:rearrange_bands
gdal:retile
gdal:rgbtopct
gdal:roughness
gdal:sieve
gdal:slope
gdal:tileindex
gdal:tpitopographicpositionindex
gdal:translate
gdal:triterrainruggednessindex
gdal:warpreproject
grass7:i.albedo
grass7:i.aster.toar
grass7:i.atcorr
grass7:i.biomass
grass7:i.cca
grass7:i.cluster
grass7:i.colors.enhance
grass7:i.eb.eta
grass7:i.eb.evapfr
grass7:i.eb.hsebal01.coords
grass7:i.eb.netrad
grass7:i.eb.soilheatflux
grass7:i.emissivity
grass7:i.evapo.mh
grass7:i.evapo.pm
grass7:i.evapo.pt
grass7:i.evapo.time
grass7:i.fft
grass7:i.gensig
grass7:i.gensigset
grass7:i.group
grass7:i.his.rgb
grass7:i.ifft
grass7:i.image.mosaic
grass7:i.in.spotvgt
grass7:i.landsat.acca
grass7:i.landsat.toar
grass7:i.maxlik
grass7:i.modis.qc
grass7:i.oif
grass7:i.pansharpen
grass7:i.pca
grass7:i.rgb.his
grass7:i.segment
grass7:i.smap
grass7:i.tasscap
grass7:i.topo.coor.ill
grass7:i.topo.corr
grass7:i.vi
grass7:i.zc
grass7:m.cogo
grass7:nviz
grass7:r.basins.fill
grass7:r.blend.combine
grass7:r.blend.rgb
grass7:r.buffer
grass7:r.buffer.lowmem
grass7:r.carve
grass7:r.category
grass7:r.category.out
grass7:r.circle
grass7:r.clump
grass7:r.coin
grass7:r.colors
grass7:r.colors.out
grass7:r.colors.stddev
grass7:r.composite
grass7:r.contour
grass7:r.cost
grass7:r.covar
grass7:r.cross
grass7:r.describe
grass7:r.distance
grass7:r.drain
grass7:r.fill.dir
grass7:r.fill.stats
grass7:r.fillnulls
grass7:r.flow
grass7:r.grow
grass7:r.grow.distance
grass7:r.gwflow
grass7:r.his
grass7:r.horizon
grass7:r.horizon.height
grass7:r.in.lidar
grass7:r.in.lidar.info
grass7:r.info
grass7:r.kappa
grass7:r.lake
grass7:r.latlong
grass7:r.li.cwed
grass7:r.li.cwed.ascii
grass7:r.li.dominance
grass7:r.li.dominance.ascii
grass7:r.li.edgedensity
grass7:r.li.edgedensity.ascii
grass7:r.li.mpa
grass7:r.li.mpa.ascii
grass7:r.li.mps
grass7:r.li.mps.ascii
grass7:r.li.padcv
grass7:r.li.padcv.ascii
grass7:r.li.padrange
grass7:r.li.padrange.ascii
grass7:r.li.padsd
grass7:r.li.padsd.ascii
grass7:r.li.patchdensity
grass7:r.li.patchdensity.ascii
grass7:r.li.patchnum
grass7:r.li.patchnum.ascii
grass7:r.li.pielou
grass7:r.li.pielou.ascii
grass7:r.li.renyi
grass7:r.li.renyi.ascii
grass7:r.li.richness
grass7:r.li.richness.ascii
grass7:r.li.shannon
grass7:r.li.shannon.ascii
grass7:r.li.shape
grass7:r.li.shape.ascii
grass7:r.li.simpson
grass7:r.li.simpson.ascii
grass7:r.mapcalc
grass7:r.mask.rast
grass7:r.mask.vect
grass7:r.mfilter
grass7:r.mode
grass7:r.neighbors
grass7:r.null
grass7:r.out.ascii
grass7:r.out.gridatb
grass7:r.out.mat
grass7:r.out.mpeg
grass7:r.out.png
grass7:r.out.pov
grass7:r.out.ppm
grass7:r.out.ppm3
grass7:r.out.vrml
grass7:r.out.vtk
grass7:r.out.xyz
grass7:r.param.scale
grass7:r.patch
grass7:r.plane
grass7:r.profile
grass7:r.proj
grass7:r.quant
grass7:r.quantile
grass7:r.random
grass7:r.random.cells
grass7:r.random.surface
grass7:r.reclass
grass7:r.reclass.area
grass7:r.recode
grass7:r.regression.line
grass7:r.regression.multi
grass7:r.relief
grass7:r.relief.scaling
grass7:r.report
grass7:r.resamp.bspline
grass7:r.resamp.filter
grass7:r.resamp.interp
grass7:r.resamp.rst
grass7:r.resamp.stats
grass7:r.resample
grass7:r.rescale
grass7:r.rescale.eq
grass7:r.rgb
grass7:r.ros
grass7:r.series
grass7:r.series.accumulate
grass7:r.series.interp
grass7:r.shade
grass7:r.sim.sediment
grass7:r.sim.water
grass7:r.slope.aspect
grass7:r.solute.transport
grass7:r.spread
grass7:r.spreadpath
grass7:r.statistics
grass7:r.stats
grass7:r.stats.quantile.out
grass7:r.stats.quantile.rast
grass7:r.stats.zonal
grass7:r.stream.extract
grass7:r.sun
grass7:r.sunhours
grass7:r.sunmask.datetime
grass7:r.sunmask.position
grass7:r.surf.area
grass7:r.surf.contour
grass7:r.surf.fractal
grass7:r.surf.gauss
grass7:r.surf.idw
grass7:r.surf.random
grass7:r.terraflow
grass7:r.texture
grass7:r.thin
grass7:r.tile
grass7:r.tileset
grass7:r.to.vect
grass7:r.topidx
grass7:r.topmodel
grass7:r.topmodel.topidxstats
grass7:r.transect
grass7:r.univar
grass7:r.uslek
grass7:r.usler
grass7:r.viewshed
grass7:r.volume
grass7:r.walk.coords
grass7:r.walk.points
grass7:r.walk.rast
grass7:r.water.outlet
grass7:r.watershed
grass7:r.what.color
grass7:r.what.coords
grass7:r.what.points
grass7:v.buffer
grass7:v.build.check
grass7:v.build.polylines
grass7:v.class
grass7:v.clean
grass7:v.cluster
grass7:v.db.select
grass7:v.decimate
grass7:v.delaunay
grass7:v.dissolve
grass7:v.distance
grass7:v.drape
grass7:v.edit
grass7:v.extract
grass7:v.extrude
grass7:v.generalize
grass7:v.hull
grass7:v.in.ascii
grass7:v.in.dxf
grass7:v.in.e00
grass7:v.in.geonames
grass7:v.in.lidar
grass7:v.in.lines
grass7:v.in.mapgen
grass7:v.in.wfs
grass7:v.info
grass7:v.kcv
grass7:v.kernel.rast
grass7:v.kernel.vector
grass7:v.lidar.correction
grass7:v.lidar.edgedetection
grass7:v.lidar.growing
grass7:v.mkgrid
grass7:v.neighbors
grass7:v.net
grass7:v.net.alloc
grass7:v.net.allpairs
grass7:v.net.bridge
grass7:v.net.centrality
grass7:v.net.components
grass7:v.net.connectivity
grass7:v.net.distance
grass7:v.net.flow
grass7:v.net.iso
grass7:v.net.nreport
grass7:v.net.path
grass7:v.net.report
grass7:v.net.salesman
grass7:v.net.spanningtree
grass7:v.net.steiner
grass7:v.net.timetable
grass7:v.net.visibility
grass7:v.normal
grass7:v.out.ascii
grass7:v.out.dxf
grass7:v.out.postgis
grass7:v.out.pov
grass7:v.out.svg
grass7:v.out.vtk
grass7:v.outlier
grass7:v.overlay
grass7:v.pack
grass7:v.parallel
grass7:v.patch
grass7:v.perturb
grass7:v.proj
grass7:v.qcount
grass7:v.random
grass7:v.rast.stats
grass7:v.reclass
grass7:v.rectify
grass7:v.report
grass7:v.sample
grass7:v.segment
grass7:v.select
grass7:v.split
grass7:v.surf.bspline
grass7:v.surf.idw
grass7:v.surf.rst
grass7:v.to.3d
grass7:v.to.lines
grass7:v.to.points
grass7:v.to.rast
grass7:v.transform
grass7:v.type
grass7:v.univar
grass7:v.vect.stats
grass7:v.voronoi
grass7:v.what.rast
grass7:v.what.vect
qgis:addfieldtoattributestable
qgis:advancedpythonfieldcalculator
qgis:aggregate
qgis:aspect
qgis:barplot
qgis:basicstatisticsforfields
qgis:boxplot
qgis:buildvirtualvector
qgis:checkvalidity
qgis:concavehull
qgis:convertgeometrytype
qgis:countpointsinpolygon
qgis:createattributeindex
qgis:createconstantrasterlayer
qgis:creategrid
qgis:createpointslayerfromtable
qgis:createspatialindex
qgis:definecurrentprojection
qgis:delaunaytriangulation
qgis:deletecolumn
qgis:deleteduplicategeometries
qgis:densifygeometries
qgis:densifygeometriesgivenaninterval
qgis:distancematrix
qgis:distancetonearesthublinetohub
qgis:distancetonearesthubpoints
qgis:eliminateselectedpolygons
qgis:executesql
qgis:exportaddgeometrycolumns
qgis:extractspecificvertices
qgis:fieldcalculator
qgis:findprojection
qgis:generatepointspixelcentroidsalongline
qgis:generatepointspixelcentroidsinsidepolygons
qgis:geometrybyexpression
qgis:heatmapkerneldensityestimation
qgis:hillshade
qgis:hypsometriccurves
qgis:idwinterpolation
qgis:importintopostgis
qgis:importintospatialite
qgis:joinattributesbylocation
qgis:joinbylocationsummary
qgis:keepnbiggestparts
qgis:knearestconcavehull
qgis:linestopolygons
qgis:listuniquevalues
qgis:meanandstandarddeviationplot
qgis:minimumboundinggeometry
qgis:nearestneighbouranalysis
qgis:orthogonalize
qgis:pointsalonglines
qgis:pointsdisplacement
qgis:pointstopath
qgis:polarplot
qgis:poleofinaccessibility
qgis:polygonfromlayerextent
qgis:polygonize
qgis:polygonstolines
qgis:postgisexecuteandloadsql
qgis:postgisexecutesql
qgis:randomextract
qgis:randomextractwithinsubsets
qgis:randompointsalongline
qgis:randompointsinextent
qgis:randompointsinlayerbounds
qgis:randompointsinsidepolygons
qgis:randomselection
qgis:randomselectionwithinsubsets
qgis:rastercalculator
qgis:rasterize
qgis:rasterlayerhistogram
qgis:rasterlayerstatistics
qgis:rastersampling
qgis:rectanglesovalsdiamondsfixed
qgis:rectanglesovalsdiamondsvariable
qgis:refactorfields
qgis:regularpoints
qgis:relief
qgis:ruggednessindex
qgis:scatter3dplot
qgis:selectbyattribute
qgis:selectbyexpression
qgis:serviceareafromlayer
qgis:serviceareafrompoint
qgis:setmvalue
qgis:setstyleforrasterlayer
qgis:setstyleforvectorlayer
qgis:setzvalue
qgis:singlesidedbuffer
qgis:slope
qgis:snapgeometries
qgis:spatialiteexecutesql
qgis:splitvectorlayer
qgis:statisticsbycategories
qgis:sumlinelengths
qgis:texttofloat
qgis:tininterpolation
qgis:topologicalcoloring
qgis:truncatetable
qgis:variabledistancebuffer
qgis:vectorlayerhistogram
qgis:vectorlayerscatterplot
qgis:voronoipolygons
qgis:zonalstatistics
saga:accumulatedcost
saga:accumulatedcostanisotropic
saga:accumulatedcostisotropic
saga:accumulationfunctions
saga:addcoordinatestopoints
saga:addindicatorfieldsforcategories
saga:addpointattributestopolygons
saga:addpolygonattributestopoints
saga:addrastervaluestofeatures
saga:addrastervaluestopoints
saga:aggregate
saga:aggregatepointobservations
saga:aggregationindex
saga:analyticalhierarchyprocess
saga:analyticalhillshading
saga:angmap
saga:angulardistanceweighted
saga:artificialneuralnetworkclassificationopencv
saga:aspectslopegrid
saga:automatedcloudcoverassessment
saga:averagewithmask1
saga:averagewithmask2
saga:averagewiththereshold1
saga:averagewiththereshold2
saga:averagewiththereshold3
saga:basicterrainanalysis
saga:binaryerosionreconstruction
saga:bioclimaticvariables
saga:boostingclassificationopencv
saga:bsplineapproximation
saga:burnstreamnetworkintodem
saga:catchmentarea
saga:catchmentareaflowtracing
saga:catchmentarearecursive
saga:categoricalcoincidence
saga:cellbalance
saga:changedatastorage
saga:changedateformat
saga:changedetection
saga:changetimeformat
saga:channelnetwork
saga:channelnetworkanddrainagebasins
saga:clippointswithpolygons
saga:cliprasterwithpolygon
saga:closegaps
saga:closegapswithspline
saga:closegapswithstepwiseresampling
saga:closeonecellgaps
saga:clusteranalysis
saga:clusteranalysisshapes
saga:concentration
saga:confusionmatrixpolygonsgrid
saga:confusionmatrixtwogrids
saga:connectivityanalysis
saga:constantgrid
saga:contourlines
saga:convergenceindex
saga:convergenceindexsearchradius
saga:convertdatastoragetype
saga:convertlinestopoints
saga:convertlinestopolygons
saga:convertmultipointstopoints
saga:convertpointstolines
saga:convertpolygonlineverticestopoints
saga:convertpolygonstolines
saga:convexhull
saga:covereddistance
saga:createlinesgraticule
saga:createpointgrid
saga:createpolygonsgraticule
saga:croptodata
saga:crossclassificationandtabulation
saga:crossprofiles
saga:curvatureclassification
saga:cutvectorlayer
saga:decisiontreeclassificationopencv
saga:destriping
saga:destripingwithmask
saga:difference
saga:diffusepollutionrisk
saga:diffusivehillslopeevolutionadi
saga:diffusivehillslopeevolutionftcs
saga:directionalaverage
saga:directionalstatisticsforrasterlayer
saga:distancematrix
saga:distancevigra
saga:diurnalanisotropicheating
saga:diversityofcategories
saga:downslopedistancegradient
saga:dtmfilterslopebased
saga:earthsorbitalparameters
saga:edgecontamination
saga:edgedetectionvigra
saga:effectiveairflowheights
saga:enhancedvegetationindex
saga:enumeratetablefield
saga:fastregiongrowingalgorithm
saga:fastrepresentativeness
saga:featureextents
saga:fieldstatistics
saga:fillgapsinrecords
saga:fillsinks
saga:fillsinksqmofesp
saga:fillsinkswangliu
saga:fillsinksxxlwangliu
saga:findfieldofextremevalue
saga:fireriskanalysis
saga:fitnpointsinpolygon
saga:fixeddistancebuffer
saga:flatdetection
saga:flattenpolygonlayer
saga:flowaccumulationqmofesp
saga:flowpathlength
saga:flowwidthandspecificcatchmentarea
saga:fourierfiltervigra
saga:fouriertransformationopencv
saga:fouriertransforminversevigra
saga:fouriertransformrealvigra
saga:fouriertransformvigra
saga:fragmentationalternative
saga:fragmentationclassesfromdensityandconnectivity
saga:fragmentationstandard
saga:function
saga:functionfit
saga:fuzzify
saga:fuzzyintersectionand
saga:fuzzylandformelementclassification
saga:fuzzyunionor
saga:gaussianfilter
saga:generateshapes
saga:geodesicmorphologicalreconstruction
saga:geographiccoordinategrids
saga:geometricfigures
saga:globalmoransiforrasterlayer
saga:gradientvectorfromcartesiantopolarcoordinates
saga:gradientvectorfrompolartocartesiancoordinates
saga:gradientvectorsfromdirectionalcomponents
saga:gradientvectorsfromdirectionandlength
saga:gradientvectorsfromsurface
saga:gridcombination
saga:gridstatisticsforpoints
saga:gwrformultiplepredictorlayers
saga:gwrformultiplepredictors
saga:gwrformultiplepredictorsgriddedmodeloutput
saga:gwrforsinglepredictorgriddedmodeloutput
saga:gwrforsinglepredictorlayer
saga:histogramsurface
saga:hypsometry
saga:imcorrfeaturetracking
saga:interpolatecubicspline
saga:intersect
saga:inversedistanceweightedinterpolation
saga:invertdatanodata
saga:invertgrid
saga:isodataclusteringforgrids
saga:kerneldensityestimation
saga:kmeansclusteringforgrids
saga:knearestneighboursclassificationopencv
saga:lakeflood
saga:landsurfacetemperature
saga:landusescenariogenerator
saga:laplacianfilter
saga:layerofextremevalue
saga:leastcostpaths
saga:linedissolve
saga:linepolygonintersection
saga:lineproperties
saga:linesimplification
saga:linesmoothing
saga:localminimaandmaxima
saga:lsfactor
saga:lsfactorfieldbased
saga:majorityfilter
saga:massbalanceindex
saga:maximumentropypresenceprediction
saga:maximumflowpathlength
saga:mergevectorlayers
saga:meshdenoise
saga:metricconversions
saga:minimumdistanceanalysis
saga:mirrorgrid
saga:modifedquadraticshepard
saga:modifiedquadraticshepardinterpolation
saga:monthlyglobalbylatitude
saga:morphologicalfilter
saga:morphologicalfilteropencv
saga:morphologicalfiltervigra
saga:morphometricfeatures
saga:morphometricprotectionindex
saga:mosaicrasterlayers
saga:multibandvariation
saga:multidirectionleefilter
saga:multilevelbsplineinterpolation
saga:multilevelbsplineinterpolationforcategories
saga:multilevelbsplineinterpolationfromraster
saga:multiplelinearregressionanalysis
saga:multiplelinearregressionanalysisshapes
saga:multipleregressionanalysisgridandpredictorgrids
saga:multipleregressionanalysispointsandpredictorgrids
saga:multipleregressionanalysispointsraster
saga:multipleregressionanalysisrasterraster
saga:multiresolutionindexofvalleybottomflatnessmrvbf
saga:naturalneighbour
saga:nearestneighbour
saga:normalbayesclassificationopencv
saga:orderedweightedaveraging
saga:ordinarykriging
saga:overlandflowdistancetochannelnetwork
saga:overlandflowkinematicwaved8
saga:paramemeltonruggednessnumber
saga:patching
saga:patternanalysis
saga:petafterhargreavesgrid
saga:petafterhargreavestable
saga:pointdistances
saga:pointsfilter
saga:pointstatisticsforpolygons
saga:pointsthinning
saga:polartocartesiancoordinates
saga:polygoncentroids
saga:polygonclipping
saga:polygondissolveallpolygons
saga:polygondissolvebyattribute
saga:polygonidentity
saga:polygonlineintersection
saga:polygonpartstoseparatepolygons
saga:polygonproperties
saga:polygonselfintersection
saga:polygonshapeindices
saga:polygonstoedgesandnodes
saga:polygonunion
saga:polygonupdate
saga:polynomialregression
saga:principlecomponentsanalysis
saga:profilefrompointstable
saga:profilesfromlines
saga:proximityraster
saga:quadtreestructuretopolygons
saga:radiusofvarianceraster
saga:randomfield
saga:randomforestclassificationopencv
saga:randomforestpresencepredictionvigra
saga:randomterraingeneration
saga:rankfilter
saga:rasterbuffer
saga:rastercalculator
saga:rastercellindex
saga:rasterdifference
saga:rasterdivision
saga:rasterize
saga:rastermasking
saga:rasternormalisation
saga:rasterorientation
saga:rasterproduct
saga:rasterproximitybuffer
saga:rasterskeletonization
saga:rasterssum
saga:rasterstandardisation
saga:rasterstatisticsforpolygons
saga:rastervaluestopoints
saga:rastervaluestopointsrandomly
saga:rastervolume
saga:realsurfacearea
saga:reclassifyvalues
saga:reclassifyvaluessimple
saga:regressionanalysis
saga:regressionanalysispointsandpredictorgrid
saga:regressionkriging
saga:relativeheightsandslopepositions
saga:removeduplicatepoints
saga:removesmallpixelclumpstonodata
saga:representativeness
saga:resampling
saga:resamplingfilter
saga:residualanalysis
saga:rgbcomposite
saga:riverbasin
saga:rivergridgeneration
saga:runningaverage
saga:sagawetnessindex
saga:seededregiongrowing
saga:seedgeneration
saga:separatepointsbydirection
saga:sharedpolygonedges
saga:shrinkandexpand
saga:sievingclasses
saga:simplefilter
saga:simplefilterwithinshapes
saga:simplekriging
saga:simpleregiongrowing
saga:simulation
saga:singlevaluedecompositionopencv
saga:sinkdrainageroutedetection
saga:sinkremoval
saga:skyviewfactor
saga:slopeaspectcurvature
saga:slopelength
saga:slopelimitedflowaccumulation
saga:smoothingvigra
saga:snappointstogrid
saga:snappointstolines
saga:snappointstopoints
saga:soiltextureclassification
saga:spatialpointpatternanalysis
saga:splitlinesatpoints
saga:splitlineswithlines
saga:splitrgbbands
saga:splitshapeslayerrandomly
saga:statisticsforrasters
saga:strahlerorder
saga:streampowerindex
saga:successiveflowrouting
saga:supervisedclassification
saga:supervisedclassificationforgrids
saga:supervisedclassificationforshapes
saga:supportvectormachineclassificationopencv
saga:surfaceandgradient
saga:surfacegradientandconcentration
saga:surfacespecificpoints
saga:svmclassification
saga:symmetricaldifference
saga:tasseledcaptransformation
saga:tcilow
saga:terrainmapview
saga:terrainruggednessindextri
saga:terrainsurfaceclassificationiwahashiandpike
saga:terrainsurfaceconvexity
saga:terrainsurfacetexture
saga:thiessenpolygons
saga:thinplatespline
saga:thinplatesplinetin
saga:thresholdrasterbuffer
saga:topofatmospherereflectance
saga:topographiccorrection
saga:topographicopenness
saga:topographicpositionindextpi
saga:topographicwetnessindextwi
saga:tpibasedlandformclassification
saga:transectthroughpolygonshapefile
saga:transformvectorlayer
saga:transposerasterlayers
saga:triangulation
saga:universalkriging
saga:upslopeanddownslopecurvature
saga:upslopearea
saga:userdefinedfilter
saga:valleyandridgedetectiontophatapproach
saga:valleydepth
saga:variabledistancebuffer
saga:variogramcloud
saga:variogramsurface
saga:vectorisinggridclasses
saga:vectorruggednessmeasurevrm
saga:vegetationindexdistancebased
saga:vegetationindexslopebased
saga:verticaldistancetochannelnetwork
saga:warpingshapes
saga:waterretentioncapacity
saga:watershedbasins
saga:watershedsegmentation
saga:watershedsegmentationvigra
saga:windeffect
saga:windexpositionindex
saga:zonalmultipleregressionanalysispointsandpredictorgrids
saga:zonalrasterstatistics

Answer 1

I had the same issue. Following this post, I resolved it by adding the following lines of code before calling the native algorithm:

from qgis.analysis import QgsNativeAlgorithms

QgsApplication.processingRegistry().addProvider(QgsNativeAlgorithms())