It's nowhere near Marvelous Designer. Marvelous Designer is for making 3D clothing for games, animation, and such. It's a limited version of Clo[1] , which is for making real-world clothing. Clo lets you design clothing, put it on an avatar, and watch it move and drape with clothing physics. It looks real. When you see good clothing in a game, it was probably created with Marvelous Designer.

Then Clo exports a file for fabric cutting compliant with the ASTM D6673-10 standard, Standard Practice for Sewn Pattern Data Interchange, which is used for the production of garment patterns. It's kind of clunky, being based on Autodesk DXF, AutoCAD's export format from the 1980s, but it's what the industry uses. You can bring such files into anything that reads DXF and view them. So a widely used formal descriptive language for fabric cutting already exists. You can send those files to a contract garment manufacturer and get garments back.

Marvelous Designer is just Clo minus the cutting pattern export feature.

[1] https://www.clo3d.com/en/

[2] https://www.normsplash.com/Samples/ASTM/191361149/ASTM-D6673...