Take a look at a thorough guide to exporting from Marvelous Designer by Olivier Couston.
People asked about my workflow on Cammy’s clothes, so here it is. Yes, it’s overly complicated, but it works. Keep in mind this is aimed at animation/VFX production pipeline, where the meshes need to be rigged, animated and the details should only be generated with displacement at render time. If you’re only trying to render a single image or going to redo the topology in real time, it’s probably overkill. Most of the time, a quick Zremesher in Zbrush would do.
Here goes the tutorial:
The guide was originally published on ArtStation.