The built-in VVC decoder is dreadfully slow (a ton of optimizations are missing), VVdec is at least 2-3 times faster on anything having AVX2/SSE4.

If you really want to give VVC a try, better stay with version 6.1.1 as it's the last one which has patches for enabling VVdec. You won't be able to apply them to version 7.0/git master:

https://github.com/fraunhoferhhi/vvenc/wiki/FFmpeg-Integrati...