Right now, capes and other textiles come through the template as the same plastic material as almost everything else. Ify ou want fewer reflections you could use a rubber material in the workshop before export, or use a color not found elsewhere in your model so you can tamper with all the nodes of the piece.

Hello,
Like pointed out by Umbramanis, there are currently no dedicated materials for textiles and therefore it will be rendered with the default material selected in the workshop. You will need to create your own material in your rendering software.
Maybe it's a project for someone here who could create a node set up for Blender that we could just copy and paste?