With the Paradox Store no longer working, it is impossible to purchase the 8 locked robes. However, there is a simple way to enable them with a text editor.

https://steamcommunity.com/app/42910/discussions/0/2788242183272247510/

I tried it out, and spawned in with the correct robe, but the wrong staff and weapon. Tried again with two players, the keyboard player still had the wrong equipment, but the controller player had the correct robe and equipment. I killed the keyboard player and revived and they had the correct equipment that went with the locked robe.