Comment by zigzag312
9 hours ago
https://github.com/sc0ty/subsync
It can sync from audio in the video or from another srt. Target srt can be in different language than reference.
EDIT: Two forks, but I haven't tried them as I'm still using the original as it still works well even though it has been archived.
I think the original SubSync was the useless linear tool I tried last time. Though the Sefzz15 fork added some kind of "piecewise" feature which might work.
No, it finds over a hundred of sync points it can match with the translated subtitle (either via reference subtitle or audio track). How the interpolation between the sync points is done I haven't checked, but it fixes gradual drifts, offsets, gaps, etc. It syncs basically everything.