Based on a brief and expertly placed bit of dialogue during a walk and talk between Carisi and Rollins, SVU and Nine-Nine sharing a universe could be possible!
A crossover would be neat, although the tone of one of the shows would have to be wildly different.
If you just went from Law & Order: SVU’s famous theme song punch of “dun dun” to “Duh duh-da!” you are not alone!
There have been more seemingly challenging crossovers bandied about before.