In a fanfic, their different origins could play a big part. Naruto, an orphan ostracized by his village at first, and Superman, an alien orphan. They could bond over their shared feelings of being alone at the start. Superman could teach Naruto about his Kryptonian heritage and how to embrace it, while Naruto could show Superman how he overcame the hatred in his village and turned it into love and loyalty.
One interesting crossover could be Naruto learning about Superman's powers. Maybe Naruto is intrigued by Superman's ability to fly and his super strength. He might try to incorporate some of those elements into his own jutsu training. For example, he could study how Superman uses his strength in combat and adapt it to his taijutsu.
Well, in some fanfiction, Superman might teach the Avengers about his Kryptonian technology. This could lead to new inventions within the Avengers' world. Also, a crossover could involve Superman's nemesis, Lex Luthor, teaming up with one of the Avengers' villains, like Ultron. It would create a really complex and exciting plot with two brilliant minds causing chaos for both Superman and the Avengers.
Well, a great crossover idea in naruto and marvel fanfic is the Avengers team coming to the Naruto world. Imagine Iron Man trying to figure out the chakra system while Captain America is learning ninja techniques. This would bring a whole new dynamic to both universes as they interact and learn from each other.
One interesting crossover could be the combination of Naruto's ninja skills with Bayonetta's witch powers. For example, Naruto could use his shadow clones in a fight while Bayonetta uses her summoned demons. They might team up to face a powerful enemy that threatens both their worlds. Maybe a villain from the Naruto universe that has some connection to the forces of evil in Bayonetta's world.
One interesting crossover could be Naruto characters trying to catch Pokemon. For example, Naruto might see a Pikachu and think it's some kind of strange new summon. He'd probably try to befriend it in his own energetic way. Another could be the Pokemon trainers coming to the Naruto world and being amazed by the ninja abilities. They might try to learn some ninja techniques, like how to walk on water or climb trees easily.
One interesting crossover could be Superman visiting Hogwarts. He might be amazed by the magic there. Maybe he tries to learn some spells, but his superpowers interfere. For example, when he tries to use a levitation charm, his super strength makes the object fly out of control.
A possible crossover could involve the Pitch Perfect characters getting some ninja training from Naruto and his friends. Imagine the Bellas trying to learn stealth and combat skills while still maintaining their musical harmony. They could use their voices in a new way, like creating sonic attacks similar to some of the jutsu in Naruto. And Naruto could learn about the power of music in bringing people together, which is something that could be really useful in his own quest to unite the ninja villages.
In an Avatar x Naruto fanfic, there could be a plot where the Avatar is reincarnated into the Naruto world. The Avatar would have to learn about chakra and ninjutsu while also trying to keep their bending abilities a secret. They could form unique bonds with Naruto characters. For instance, they might team up with Sasuke to explore the similarities between the Uchiha's Sharingan and the Avatar's connection to past lives. Or they could help Sakura with her medical ninjutsu by using their knowledge of herbs and healing from the Avatar world.
In a Naruto - James Bond fanfic, there could be a scenario where Bond is on a mission in a place that has some sort of connection to the Naruto universe. Maybe it's a place where there are ancient ninja artifacts. Naruto, being an expert in all things ninja - related, could be called upon to help Bond. They could have a lot of interesting interactions, like Naruto being amazed by Bond's cool gadgets, and Bond being intrigued by Naruto's chakra - based powers.
One interesting crossover could be Naruto learning some of the X - Men's powers. For example, he might gain the ability to control magnetism like Magneto and use it in combination with his own chakra control for unique attacks.