Are there DP-HDMI adapters that work with HD audio bitstreaming and VRR? Different use case, but I've not had much luck finding good options.
https://www.reddit.com/r/linux_gaming/comments/1pkdfcm/ugree...
It was all the rage towards getting 4K 120 Hz VRR on Linux before AMD came along to contribute proper HDMI 2.1 support to the kernel. There is also mention in that thread of a CableMatters adapter that could be flashed with an alternate firmware but it wasn't as stable.