Show A is fictional in Show B and Show B is fictional in Show A

I'm trying to figure out what to call this. There is a paradox (not a trope apparently) called Mutually Fictional but according to that page, it specifically doesn't cover this situation, and gives no further reference.

Still, this situation seems paradoxical to me. In this case, if people from Show A watch Show B, they could see an episode that references Show A and themselves.

Is there a name for this?

Lost And Found is the place for finding tropes. It seems like you're looking for an In-Universe version of Celebrity Paradox.