Update: DXVK-NVAPI 0.7 was also released just now with NVIDIA Reflex for D3D12 support using the VKD3D-Proton entry points. There is also support for Latencyflex on non-NVIDIA GPUs for a few games via spoofing the Pascal architecture for non-NVIDIA GPUs. Plus various other updates and improvements.
VRR has no performance impact, it would only reduce latency. Traditional vsync is optional on top of that and only matters if you are above your vrr range. And at the point of >120fps generally I think the delay of one frame is irrelevant.