Perhaps a powerful artifact in the Marvel universe starts causing chaos similar to the effects of the Shikon Jewel. Inuyasha's group has experience with such powerful and dangerous items. The Avengers, being the protectors of their world, reach out to Inuyasha and his friends. Black Widow could use her espionage skills to help Inuyasha track down the source of the trouble, while Hulk could provide the brute force needed in battles against the new threats created by this strange crossover.
One possible plot could be that the Shikon Jewel gets scattered across the Marvel universe. Inuyasha and his friends, like Kagome, have to team up with the Avengers to retrieve the pieces. Iron Man might be intrigued by Inuyasha's sword and try to study it, while Captain America could admire Inuyasha's fighting spirit. They'd face villains who also want the power of the Shikon Jewel, creating an epic adventure.
The plot could involve a spell gone wrong that merges the worlds of Inuyasha and the Avengers. Inuyasha might find himself in New York and be mistaken for a new kind of threat. Thor could sense a kind of otherworldly power in Inuyasha and initially be on guard. But as they learn about the situation, they join forces. Maybe the Avengers help Inuyasha deal with some of his old enemies like Naraku who have also been affected by this strange merging of worlds.
One possible plot could be that Inuyasha somehow gets transported to the Twilight world. He might initially be confused by the modern settings and the presence of vampires and werewolves. Bella could mistake him for a new type of supernatural being. And Inuyasha, with his sword and combat skills, could get involved in the ongoing feud between the Cullens and the werewolves in Forks.
Characterization can be tough. Each character from both series has their own distinct personality. The Avengers have their own dynamics, and Inuyasha has his own temperamental nature. When bringing them together, the writer has to ensure that the characters stay true to themselves while also developing new relationships. For instance, Captain America's sense of justice might clash with Inuyasha's more self - centered approach to fighting at first.
One possible plot could be that a character from Naruto with the Rinnegan somehow gets transported to the Inuyasha universe. Maybe they team up with Inuyasha and his friends to fight a common enemy. For example, the power of the Rinnegan could be used to counter some of the powerful demons in the Inuyasha world. The character might also introduce new jutsu or abilities to the Inuyasha gang, which could change the way they fight battles.
One possible plot could be that Thor somehow gets transported to the Inuyasha universe. Thor's powerful hammer and lightning powers would be a huge asset or a source of conflict. Maybe the demons in the Inuyasha world see Thor as a threat or a powerful ally to be manipulated. Inuyasha and his group might initially be wary of Thor but then realize they can work together to defeat a common enemy, like a powerful demon that is causing chaos across the land.
A plot could involve a spell gone wrong in the Inuyasha world that opens a portal to the Disney realm. Kagome, being from a more modern world, recognizes some of the Disney elements. Mickey Mouse could be the first Disney character they meet. He helps them navigate this new world while Inuyasha is trying to find a way back home. Meanwhile, Disney villains might see Inuyasha as a threat and try to get rid of him. But Inuyasha, with his combat skills, manages to fend them off. In the end, they find a way to close the portal and return home, but not before creating some new friendships and memories.
Well, one possible plot could be that Rick accidentally opens a portal to the Inuyasha universe while trying to find a new energy source. Morty gets dragged along and they meet Inuyasha and his gang. Maybe Rick's advanced technology could be mistaken for some kind of powerful magic by the characters in the Inuyasha world. And Morty could befriend Shippo, since they are both kind of the sidekicks in their respective groups.
Well, one possibility could be that the characters from Ice Age end up in the feudal Japan setting of Inuyasha. Sid could befriend Shippo, the fox demon. They might get into all sorts of comical situations together, like trying to find food in a world full of yokai. Manny, the mammoth, could be mistaken for a strange demon by some of the more superstitious villagers. And Diego might team up with Inuyasha to fight a common enemy, perhaps a powerful ice - based demon that threatens both their worlds.
One interesting plot could be that Naruto and his friends are on a mission and accidentally end up in Inuyasha's feudal Japan through some sort of magic portal. There, they meet Inuyasha and his group. Naruto's ninja skills could be put to the test against the demons Inuyasha usually battles. And perhaps they team up to defeat a powerful common enemy, like a super - strong demon that neither group could handle alone.
The plot could involve the Juubi's chakra influencing some of the demons in the Inuyasha world. Naruto arrives and has to figure out how to stop this chaos. He might teach Inuyasha some of his ninja skills, and Inuyasha in turn could show Naruto how to deal with the demons. They could also find that the Juubi has some ancient connection to a powerful artifact in the Inuyasha world, and they have to stop an evil force from using this connection for their own gain.
Well, perhaps in this fanfiction, there's a multiverse rift that pulls Nightwing into the Avengers' world. The Avengers initially mistake him for an enemy, but after some misunderstandings are cleared up, they realize his skills. Together, they face a new threat created by a combination of Hydra and some of Nightwing's rogues gallery who have also crossed over. Nightwing could teach the Avengers some stealth tactics while they show him how to handle more powerful cosmic threats.