Printed without supports no problem. I would suggest mouse ears as one corner did curl a bit but still usable.
https://www.printables.com/model/147313-10-inch-patch-panel-12-keystone-module-12-u
This was the original patch model i used to adapter to this rack. I haven't gotten keystones yet but i'll try to edit once i confirm ones that work.
The author remixed this model.
I joined the panel and a patch panel i found here to create a patch panel model for this rack setup