[Warner306]

I've always wondered in the LAV video filters what is the difference between setting up
D3D11 or DVXA2 (copy-back)

 DXVA2 copy-back copies back the decoded frames to the system RAM before passing it back to the GPU.

D3D11 Native does not copy back to system.

In practice, both are about the same speed, but some madVR processing can be faster with D3D11 Native, so I would use it.

The video quality will be identical.