As other comments have suggested it's difficult to imagine that this has a lot of advantages to simply using pipes over ssh. And pipes don't need a shared filesystem either.
I suppose ssh would be tricky if you're combining multiple input files.
I suppose ssh would be tricky if you're combining multiple input files.
xargsBut with single input, single output, you can just do:
ssh destination "ffmpeg -switches" <infile >outfile find . -name '*.mkv' \
-exec bash -c \
"ssh server ffmpeg < {} > {}.transcoded.mp4" \;