Couleur

hit "code -> download zip" on the page repo, and in the plugins folder place them in vapoursynth folder

https://github.com/EleonoreMizo/fmtconv/releases

use the latest beta so you can change the container i like to use custom ffmpeg filter "-c:v utvideo" with container avi, works in vegas

Try some different combination of color range and color space in OBS' advanced settings

that is the ffmpeg statistics, maybe it is hardcoded to not show via -loglevel

see if you can use it from the command line 👍