One idea could be that a Sith Lord somehow gets transported to the MCU universe and tries to take over Hydra. They could use their dark side powers to manipulate the already corrupt organization. Another could be a story where a young Jedi in training from the Star Wars universe ends up in the MCU and teams up with the Avengers to fight a Sith who has also made their way there. Maybe they have to combine the Force with the superpowers of the Avengers to defeat the Sith.
Maybe the Flash could visit the MCU. He could race against Quicksilver. It would be a really cool showdown of speedsters from different universes. And then the Flash could get involved in an MCU - level threat, like Thanos' invasion but in a different timeline. He could use his speed to try and steal the Infinity Gauntlet from Thanos, creating a whole new plotline for a fanfiction.
A great plot could involve Spider - Man from the MCU getting lost in the DCAU and teaming up with the Teen Titans. He could teach them some of his acrobatic fighting moves while they could introduce him to some of their more out - there villains. This would be a fun way to combine the more light - hearted Teen Titans with the street - level heroics of Spider - Man.
One idea could be a crossover between a Sith Lord and a superhero universe. The Sith Lord's dark powers and manipulation skills would create an interesting dynamic against the heroes. For example, a Sith Lord in the Marvel Universe could try to turn some of the anti - heroes to the dark side.
Darth Vader would be an amazing character to include. His imposing presence and incredible power would be a huge threat in the MCU. He could face off against Thor, with their different types of powers creating an epic battle. Another interesting character would be Kylo Ren. His conflicted nature could add an interesting dynamic, especially if he interacted with characters like Captain America who have strong moral compasses.
Well, in winx mcu crossover fanfiction, a cool idea is the fusion of magic and superpowers. The Winx's magical transformations could be compared to the Hulk's transformation, in terms of a physical and power - based change. Also, the idea of the Winx attending a school like the Xavier Institute in the MCU could be really fun. They could learn about both their magic and how to coexist with mutants and superheroes.
An interesting angle could be a time - travel fanfiction. A Sith Lord from the Star Wars universe somehow travels to the Naruto world. This Sith Lord could start causing chaos and trying to recruit followers. Naruto and his team would have to learn about the Sith's powers and weaknesses quickly in order to defeat this new and powerful enemy. They might also discover some similarities between their own world's history of power struggles and that of the Sith's.
One idea could be creating a male OC who is a brilliant scientist from a small town. He discovers a new form of energy that attracts the attention of Tony Stark. Another could be a male OC with super speed who has to hide his powers until he's forced to use them to save a city. Maybe a male OC who is an alien prince stranded on Earth and has to learn about human culture while also trying to find a way back home.
Another interesting concept would be a crossover where Hogwarts is suddenly transported into the MCU universe. The students of Hogwarts have to adapt to this new world filled with superheroes and high - tech gadgets. Meanwhile, the superheroes are intrigued by the magic of Hogwarts and want to learn more about it.
One interesting concept could be the magic of Harry Potter's world interacting with the high - tech gadgets of the MCU. For example, imagine Hermione trying to figure out how Tony Stark's arc reactor works using magic. Or perhaps the Avengers having to deal with a Dementor attack. Another concept might be characters from each universe teaming up. Harry, Ron and Hermione joining forces with the Avengers to fight a common enemy like Thanos who has somehow harnessed magic as well.
One plot idea could be Ahsoka being tempted by the dark side by a Sith. Maybe she is lured with the promise of greater power to defeat an enemy. Another could be a Sith trying to use Ahsoka as a pawn in a larger scheme against the Jedi Order.