so i bought this addon for Blender to retopo marvelous designer cloth.
it works quite well, still a pain to go through it, but the end result is what
is required, ie a clean retopo'd verision of your dense triangualted cloth mesh
failry cheap for personal use anyway
https://www.youtube.com/watch?v=DgX0uwVjvKsit has a few quirks, but does work
depending on whats required, it still might better to do it by hand TBH
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