VLC and mpv literally use the same underlying codec library. (As well as ffmpeg.)

Have you tried both? mpv is able to play high resolution HEVC videos backwards at real time by holding the "previous frame" key. VLC can't reliably jump backwards even at second intervals, forget about reverse playback.

So? Here is the post where VLC dev explains why you can't seek 1 frame back (you can do that in MPC and mpv) https://forum.videolan.org/viewtopic.php?f=7&t=126609&start=...