turbid crane
I noticed Rewind already uses FFmpeg under the hood to handle codec, bitrate, and FPS, so i think they should allow custom ffmpeg flags to users who want to use more advanced features from ffmpeg like multipass, av1 codecs, and other custom ffmpeg flags like eg:
-c:v h264_nvenc -rc vbr -cq 18 -qmin 18 -qmax 18 -multipass fullres -b:v 0 -maxrate 50M -bufsize 100M -profile:v high -level 4.2
for example a window at the end for exporting where you can paste your flag in