I don’t really know. Fro googling for benchmarks it seems, that the 2080S is faster, at least for gaming. For personal preference I usually choose Quadro’s, that would mean the RTX. And yes, QuickTime videos with Animation codec should run. You can also try to render a h264 for fill and another for key. Name the key witheo the same with added _A. So if the fill video is called: myVideoClip.mov call the key myVideoClip_A.mov. You need to try, what uses less performance. Don’t use ProRes as these are performance eater.
got it, thank you didi, I will try it