This is 4 player gameplay of the mod SplitWolf running in conjunction with a wolf3d sourceport on the Rasberry Pi 3. I was playing this with some family members of mine who were not very experienced with the game (hahaha). I'm the top-left screen.
My opinion: Some issues with remapping controls. Seems to work best with a dual-shock setup; couldn't figure out how to set up strafe to left and right bumper on a simpler controller.
HUD display is a little chopped on 3 and 4 players
Minimap doesn't work at all with 3 or 4 players ( but works great on 1 and 2 players). This led to my inexperienced teammates getting lost a lot.
I learned how to set this up with this guide:
This thread helped me get the wolf3d source port to work with a full version of Wolfenstein 3D:
The 8-Bit Guy