I am using pyproj.
X/Y conversion is pretty straightforward through
transformer = Transformer.from_crs(31468, 25832,always_xy=True)
However, this does not transform the heights. From Vertical Datum transformation using Pyproj I got the impression that I might need to convert the heights with different CRS since the ones I am using are strict lateral.
I tried initializing the transformer with the corresponding codes for the ellipsoid systems
But that throws
Invalid projection: EPSG:6314: (Internal Proj Error: proj_create: crs not found)
I need help here.