In a Naruto - Hulk fanfiction, a plotline could involve the Hulk being seen as a new form of tailed beast. The ninja would be unsure how to deal with him. Naruto, on the other hand, might see similarities between the Hulk and himself when he loses control of the Nine - Tails' power. He could try to help the Hulk gain control over his rage. Or perhaps a villain from the Hulk's world follows him to the Naruto world and they have to team up to defeat this new threat.
There could also be a plotline where they both enter a mysterious tournament. They have to fight other superheroes and villains in a series of battles. Along the way, they learn more about each other's capabilities and form a stronger bond.
Perhaps there's a plot where She - Hulk is from an alternate dimension where the wizarding world and the world of superheroes co - exist. She comes to the main 'Harry Potter' dimension to seek help because her world is under threat. The Hogwarts professors and students have to work with her to find a way to save both their worlds, and along the way, there are a lot of cultural clashes and exchanges of knowledge between the two different universes.
Yes, in the realm of fanfiction, anything is possible. Fanfic writers often create wild and imaginative crossovers. They might come up with a convoluted backstory where some sort of time - traveling or interdimensional event links Naruto's world to Hulk's and creates a family connection between them.
A possible plotline could be that Calypso, with her alluring powers, tries to tempt Naruto away from his path of becoming Hokage. But Naruto, with his strong will, resists and instead tries to show Calypso the importance of having a noble goal. Another plotline might be that Naruto and Calypso team up to fight a powerful entity that is causing chaos in both their worlds.
One possible plotline could be Naruto using his new position as a daimyo to bring about political reform in the ninja world. He might try to end the long - standing feuds between different ninja villages by leveraging his power.
One possible plotline could be that Naruto dies during a great battle, like against Kaguya. But his spirit remains because he has some unfulfilled desires, like seeing the village fully at peace. So, as a ghost, he tries to influence the living to achieve that peace.
A possible plotline could be Orochimaru's redemption. He realizes the error of his ways and joins Naruto in protecting the ninja world. He could use his vast knowledge of jutsu and forbidden arts to help Naruto against new threats.
One plotline could be Naruto starts in his own world, discovers a portal to the Pokemon world, and decides to explore it. He might start as a novice Pokemon trainer and quickly rise in the ranks using his ninja skills.
One plotline could be that Naruto is chosen by Poseidon to be his champion in the human world. He is given special powers to protect the seas and their secrets from those who would misuse them. Naruto, with his determination, uses these new powers to fight off evil forces that are threatening the ocean's balance.
One plotline could be Naruto starting from the bottom in the wrestling world. He's underestimated because of his small stature or his goofy personality, but he quickly rises through the ranks with his unique fighting style that combines ninja moves with wrestling holds.