In Batman's earlier days they hinted that he was huge fan of the Shadow although as was pointed out they brought that into more recent times and changed the name of the character to the Gray Ghost who was voiced by none other than Adam West.
Cool idea and nice job. Yeah, great teamup for sure. I think DC put em together back in the 70's. I don't think they tackled any major villian though. I'm thinkin' Fu Manchu or Dracula for a villain maybe.