Well, in some Moon Knight fanfictions, Avengers might team up with Moon Knight to fight a common enemy. For example, they could be facing a powerful new villain that neither could defeat alone. This could lead to some really cool fight scenes and interesting character interactions, like Iron Man providing tech support while Moon Knight uses his unique combat skills.
A possible crossover could involve the settings. The Hidden Villages in Naruto could be the backdrop for Moon Knight's adventures. Picture Moon Knight in Konoha, dealing with the ninja politics and perhaps even learning some ninja techniques. He could team up with Naruto and the other ninjas to face a common enemy, like a new villain that combines the dark magic from Moon Knight's world with the ninja arts of Naruto's world.
One interesting crossover could be the Avengers facing a threat that requires Ben's Omnitrix powers. For example, an alien invasion that the Avengers can't handle alone. Ben could transform into Four Arms and help in hand - to - hand combat against the powerful alien foes. Another idea is that Tony Stark might be interested in the technology of the Omnitrix and try to study it, which could lead to some humorous and tense situations as Ben tries to keep his secret device safe.
A crossover might involve Sasuke from Naruto in the Vampire Knight universe. Sasuke's search for power could be paralleled with the vampires' thirst for blood or power in their own world. He could encounter the vampire hunters and perhaps form an unlikely alliance with them, seeing as he has his own vendetta against those he deems as powerful enemies. The idea of Sasuke using his Sharingan in a world full of vampires and their unique abilities would make for an exciting story.
In some fanfictions, Sailor Moon herself could team up with Captain America. Their leadership qualities would blend well. Sailor Moon's positive energy and ability to inspire could be a great boost to the Avengers' morale. Meanwhile, Captain America's combat skills and strategic thinking would be useful in the battles they face together in this crossover universe.
One interesting crossover could be a story where Sailor Moon's magic and Batman's detective skills combine to solve a super - villain mystery that spans both their universes. For example, they might team up to stop a new villain who has the ability to manipulate time, a power that is of great interest in Sailor Moon's world and a threat to Batman's Gotham.
One interesting crossover could be a scenario where the yandere character from Yandere Simulator ends up in the Vampire Knight world. Maybe she becomes infatuated with one of the vampire characters. For example, she could target Kaname Kuran and try to eliminate any rivals in a very yandere - like way, all while dealing with the complex vampire society and politics in the Vampire Knight world.
Well, a cool crossover idea in the fanfiction could be Naruto teaming up with Batman. Naruto's positive and determined attitude could influence Batman's rather brooding nature. In a fight, Naruto could use his Rasengan against the Arkham Knight's high - tech weaponry. And his shadow clone jutsu would be great for confusing the enemies in Gotham's complex alleys and rooftops.
One interesting crossover could be a scenario where the vampires from Vampire Knight attend Hogwarts. They would have to adapt to the magic system there. For example, their superhuman speed and strength might be an advantage in some magical duels, but they would also have to deal with spells like the Patronus Charm which they've never encountered. It could make for a really exciting story.
One good Stiles - Avenger crossover is 'Stiles in the Marvel Universe'. It has an interesting plot where Stiles uses his wits from the Teen Wolf world to interact with the Avengers. Another is 'Stiles and the Avengers: An Unexpected Alliance' which shows how Stiles' unique skills could be useful to the Avengers.
In Avenger - related fanfiction, Moon Knight might become more of a team player. Since the Avengers are a team, he could learn to work better with others. For example, he might start sharing more of his knowledge about the underworld and his enemies, which he was more secretive about before.