Unless you change HVE code as mentioned in HVE NVidia acceleration will not work
There is possibility that you see NVidia as VAAPI device (e.g. with vainfo) but this is NVidia VAAPI through VDPAU bridge and VDPAU is only for decoding.
AMD supports VAAPI encoding but I currently don't know about any hardware supporting 10 bit HEVC encoding.
For AMD you could look at output of:
vainfo --display drm --device /dev/dri/renderDXXX #XXX for your render node
AMD note - while you probably will not be able to hardware encode with this example on AMD, you should be able to hardware decode result starting from GCN4 (Arctic Islands) where 10 bit HEVC decoding was added.
Unless you change HVE code as mentioned in HVE NVidia acceleration will not work
There is possibility that you see NVidia as VAAPI device (e.g. with vainfo) but this is NVidia VAAPI through VDPAU bridge and VDPAU is only for decoding.
AMD supports VAAPI encoding but I currently don't know about any hardware supporting 10 bit HEVC encoding.
For AMD you could look at output of:
in the search for something along the line: