So...B&R merch and crap:
1. Does anyone remember the Batman & Robin game on Playstation? It was a not-very-good version of Arkham Knight. You could drive the batmobile in a (mostly) open world, search for clues and stuff like that. You could play as Batman, Robin and Batgirl. It had annoying camera angles, stiff animations and horrible fighting mechanics. I still liked it

You could even visit places like Axis Chemicals from the first movie, which I thought was pretty cool.
Too bad about the horrible controls and camera angles. If they had changed a few things, it could have been a really good Batman game!
2. I also had a small handheld "tiger" game that was shaped as the batsymbol. A small Batman-figure was included, and you could use it as a joystick. Can't remember if I ever beat it. I think I preferred the Batman Forever version.
3. My aunt gave me some B&R coloring books. The art reminded me very much of BTAS (I still have them at my mother's house, and since I didn't color everything, I can give them to my daughters when they get older). Anyone else know what I'm talking about.
4. From my uncle I got a bag of wine gums shaped as Batman if Robin if I remember correctly. I haven't found any info about it on the internet, but I think it was German.
5. The action figures, of course. Battle Gear Bruce Wayne, which someone stole from me, Hover Attack Batman, Jungle Venom Poison Ivy, Brain vs Brawn (two figures: Batman and Bane), and the batmobile.
6. The comic book adaptation. I read it before the movie

I didn't care about spoilers back then.
I miss the 90s...