Yep, sounds like the Sunsoft version. I need to play that version some more. I'm testing out my Mega Retron HD tonight, so I think I'll play some Batman Returns at some point.
I find there are some games that have different versions between consoles. The Adventures of Batman and Robin (based on the '90s animated series) is vastly different between the Genesis and SNES. I only found that out recently. I've had the Genesis game for ages, since way back in the day. I was in the mood to play it recently, so I popped in my 100 in 1 multi cart for the SNES and popped that game up, only to find out it's a different version. Pretty cool.