The word 'mosaic' is often used for quite different things within the worlds of ArcGIS and GDAL.
With GDAL and it's downstream applications like Qgis it is common to see mosaic used in the context of "assemble all these tiled images so they appear as one big image", with gdalbuildvrt and
gdalmerge put forth as a convenient means of getting there.
ArcGIS has the same starting point, "assemble all these tiled images so they appear as one big image", and then goes on to add "while doing so [blend, min, max, mean, sum, ...] the overlapping pixels" and a few other things.
To put in uncharitably, in this regard ArcGIS is smart and GDAL is stupid.
However it's pretty evident GDAL is not stupid, so my question is: in the GDAL and/or Qgis tool chain what is the equivalent workflow to ArcGIS mosaic?
(note, I'm not talking about the Mosaic Dataset, which is a different beast altogether)