The plot might involve the Brooklyn 99 crew getting dragged into a supernatural mystery. Like they start investigating a series of strange murders that turn out to be the work of a werewolf. Sam and Dean come to town to deal with it. Jake could be the one who first notices something really off about the case and teams up with the Winchesters.
Definitely Dean and Jake. Dean is all about the action and his tough - guy persona, while Jake is this goofy but smart detective. They could bond over their love for solving cases, though their methods are very different. Jake might be a bit freaked out by Dean's knowledge of the supernatural at first.
Maybe there's a situation where the points system in The Good Place is being hacked, and it's somehow related to a criminal in Brooklyn. The Brooklyn 99 team travels to The Good Place to investigate. As they dig deeper, they find out that it's a plot by a disgruntled former resident of The Good Place who wants to change the system. The Brooklyn 99 characters bring their own perspectives on justice and fairness, which challenges the existing beliefs in The Good Place. And there would be a lot of comical moments as the two groups interact, like Holt trying to communicate with Janet in his very formal way.
It could be a hilarious adventure. Picture the characters from Brooklyn 99 getting into the afterlife scenarios of The Good Place. Jake's antics would surely disrupt the carefully planned system of The Good Place. Maybe he'd try to outwit the points system or come up with some crazy detective work to figure out the mysteries of the afterlife there.
One creative idea is a time - travel crossover. For example, the characters of Brooklyn Nine - Nine traveling back in time to a different era, like the 1920s, and having to solve crimes while dealing with the cultural differences of that time. It's a really cool concept.
There's also a Brooklyn Nine - Nine and 'Parks and Recreation' crossover fanfiction. In it, the Pawnee gang meets the Nine - Nine crew. Amy Santiago and Leslie Knope would probably bond over their love for organization and efficiency. It's a fun read as they all get into various misadventures together.
The character interactions. When Brooklyn 99 characters cross over with others, it's always exciting to see how they'll get along. For instance, if they cross over with a show like 'New Girl', seeing Jake's detective skills contrasted with Jess's more whimsical nature can be really engaging.
One idea could be that the NCIS team is investigating a series of strange murders that seem to have a supernatural element. They end up calling in the Winchesters from Supernatural for help. The two groups initially clash due to their different methods but eventually learn from each other and solve the case together.
One idea could be that Lucifer from 'Lucifer' enters the world of 'Supernatural'. Maybe he teams up with the Winchester brothers to fight a common enemy, like a new type of demon that is causing chaos in both their realms. He could use his devilish charm and powers in a way that the Winchesters are both skeptical and intrigued by.
One popular 'brooklyn 99 crossover fanfic' could be the one where they cross over with 'The Office'. It's really interesting to see the different comedic styles blend together. The characters from Brooklyn 99 interacting with those from The Office create hilarious situations. For example, Jake's antics paired with Jim's pranks make for a really fun read.