Well, a crossover could involve Loki tricking Spider - Man into doing his bidding at first. But as Spider - Man discovers Loki's true intentions, he turns against him. However, they later find out that they were both being manipulated by a greater evil. So they have to put aside their differences and work together. This would show how two very different characters from different universes can come together for a greater good.
One interesting crossover could be Loki using his magic to create illusions during one of Spider - Man's battles in New York. This would make Spider - Man have to rely more on his spider - sense to figure out what's real and what's not. Another could be Loki teaming up with Spider - Man, perhaps reluctantly, to fight a common enemy like a powerful interdimensional being. They would have very different personalities and powers, so seeing them interact would be really cool.
In some fanfictions, there could be a crossover where Spider - Man gets caught in a time - travel experiment by the X - Men. He ends up in a past era with the early X - Men. There, he has to use his modern - day knowledge and skills to help them against a powerful foe. It could also be a crossover where the X - Men visit Spider - Man's world in Queens and learn about his normal life as Peter Parker, while also helping him fight local villains.
One interesting crossover could be Spider - Man using his web - slinging abilities in the Demon Slayer world to quickly move around and help the Demon Slayers. He could use his enhanced strength to take on powerful demons that the Demon Slayers might struggle with.
In some fanfictions, Ultron might team up with one of Spider - Man's villains, like the Green Goblin. They could create a plan to take over New York. Spider - Man would then have to face this powerful alliance. He might seek help from other superheroes he's associated with, like Iron Man or Daredevil, to combat this new threat.
One interesting crossover could be Peter Parker (Spider Man) attending U.A. High. He'd likely be an instant hit with his web - slinging skills. His sense of humor would also mesh well with the likes of Denki Kaminari. Another could be a team - up between Spider Man and Midoriya. Midoriya could learn a lot from Spider Man's experience in handling his powers.
One interesting crossover is 'When Worlds Collide'. In this fanfiction, the universes of Iron Man and Spider - Man somehow get merged. This leads to some really unique situations, like Spider - Man having to deal with Iron Man's high - tech world in a whole new way. Another is 'The Tech - Web Alliance'. Here, they form an alliance to fight a villain who is using both high - tech and some sort of web - related powers. It's a really cool concept that combines their two skill sets.
One interesting crossover could be Naruto's chakra system being studied by Spider - Man 2099's advanced scientific mind. Maybe he could find a way to use chakra - like energy in his web - slinging or combat. Another could be Naruto teaching Spider - Man 2099 some of his ninja skills, like stealth or hand - to - hand combat techniques. And a really wild one could be a fusion of their powers, where Spider - Man 2099 has some of Naruto's nine - tailed fox power in his enhanced form.
One interesting crossover could be where Spider - Man finds himself in the Twilight world. Maybe he has to deal with the vampires and werewolves while trying to keep his identity a secret. He could use his web - slinging skills to navigate the forests of Forks.
Perhaps in the fanfiction, some of the Fairy Tail characters could gain Spider - Man - like powers. Natsu, for instance, could have the ability to shoot fire - webs from his hands. This would not only add a new dimension to his fighting style but also create some really cool and unique battle scenes where he combines his fire - based attacks with web - like maneuvers.
One interesting crossover could be Spider - Man using his agility to outmaneuver the Hulk during a battle in a fanfiction. His webs could be used to slow down the Hulk's rampage.
In a Power Rangers and Spider - Man fanfiction crossover, perhaps the Green Ranger has a special connection to Spider - Man. The Green Ranger's power coin gets corrupted by some sort of dark magic from another dimension. Spider - Man, with his scientific knowledge, helps the Power Rangers figure out how to cleanse the power coin. In the process, they have to battle evil versions of the Power Rangers that are being controlled by the dark magic. The Rangers and Spider - Man use their unique abilities, like the Rangers' morphing and combat skills and Spider - Man's spider - sense and web - slinging, to overcome this threat.