Thanks so much for the help so far, unfortunately that didn’t work either.
Luckily this is all backed up to the moon and back so I’m not worrying about losing anything, it’s just frustrating to not be able to update to the most recent version of UE4 especially because a lot of the asset packs no longer support 4.21.
Okay, so I removed the crouch node and compiled, all good. Character moves normally, and even plays the crouch animation, but obviously the character movement logic is not firing so you can do things like sprint while crouching etc.
saved and closed the editor, reopened, tried to make a new Crouch node, no dice 
converted the character to a pawn, UE4 did not like that. As you said, everything broke, then I converted it back to a Character and everything was fixed (the fact that this is even possible is amazing to me) but still no crouch
I did see this curious error while the character was a Pawn. I didn’t get this for Uncrouch. It appears that it is looking for the crouch function in the character BP instead of the Base Character BP.
Is there a way we can kind of, point it back in the right direction?