Many wads listed on WADSUP can be played in-browser using Freedoom iwads and the RetroArch Web Player:
These particular wads are playable in-browser using Freedoom iwads and JS-DOS. Mouse options and such are on the left.
General info:
In PRBoom you can change your controls in the usual way, but you'll need to save your config in the RetroArch menu (PgUp + F1 to access that menu).
Since this uses FreeDoom, and FreeDoom 2 as the base(s) I can't guarantee that any sprite edits that the WADs themselves hold will be congruent with the sprites in the IWADs. Regardless you should be able to play the wads here just fine.
For some reason any cheat except level skipping (IDCLEV) freezes RetroArch.
Keyboard/Mouse only.
Discussion