Optical flow using Hybrid -- Possible?

[Selur]

-codec:v hevc_nvenc -preset 1 -rc 0 -spatial_aq 1 -bluray-compat 1 -multipass 2

Hybrid does support NVEnc through NVEncC on Windows.
Using '-rc 0' = constant quantizer and '-spatial_aq 1' spatial adaptive quantization is not supported by Hybrid since it does not make sense trying to get fluctuating quantizers ins a contstatn quantizer mode.
'-multipass 2' should be the same as '-2pass' in ffmpeg iirc. Hybrid does only support this in variable bitrate encoding mode (since that to me is the only method where is makes sense).
About NVEncCs options see: https://github.com/rigaya/NVEnc/blob/mas...ions.en.md

Since I want 'perfect'

I doubt you will get that with Interframe since it's tuned for speed even when the settings force the slowest settings.

Cu Selur