2. having some tooling that can do macro alignment, independent of metadata (for example by audio fingerprinting) for kdenlive someone also made an external tool <https://www.youtube.com/watch?v=mypKKK-Se7A>
Alignment using timecodes for Professional productions was addressed in MantisBT 448 (https://www.cinelerra-gg.org/bugtracker/view.php?id=448). The "Align timecodes" tool came into being there. But the pro who created the issue concluded: "I have tested the 'align timecodes' function in the new version and am very happy to say that is working wonderful! Along with the 'To clip' function I can now make synced up subclips. I believe that to my knowledge Cinelerra GG is now the first FLOSS video editing program to support timecode syncing with subclip functionality: that's a big premiere! Thanks to everyone involved and especially PhyllisSmith. Few notes for further improvements: - A batch function would be great, especially to already sync up the clips from the 'Resources' window. - When I use the 'align timecodes' function the timecode of the whole sequence changes to the timecode of the clip I'm syncing. I have not seen this in other editing programs and don't think this is a useful feature, I think it would be better if the timecode of the sequence stays untouched and the clips stays in place." It would be nice to be able to do alignment of various audio/video tracks with an external audio track in batch, all at once, in the Resources window, before getting to the timeline. Question: is it possible to modify and use the script linked by Stefan in CinGG?
4. export this in either some EDL format or multitrack format being NLE independent.
As for interchange between various programs, I don't think CMX3600 is viable; it is too limited and not well supported by modern programs. Nowadays AAF (https://en.wikipedia.org/wiki/Advanced_Authoring_Format) is used as an interchange format; I believe it is based on Avid MXF.