One unique element is the combination of magic and superpowers. In normal stories, these are two very different concepts. But in a crossover fanfic, seeing Iron Man's tech interact with spells from Hogwarts is really cool.
One great 'hp avengers crossover fanfic' is 'The Wizarding Avengers'. It combines the magic of Harry Potter world with the superhero powers of the Avengers in a really interesting way. The characters interact in unexpected yet engaging manners.
A common theme is the clash of different powers. The magic from Harry Potter and the superpowers of the Avengers often collide and combine in interesting ways.
Sure. 'The Wizarding World and the Avengers' is a great one. It combines the magic of Harry Potter and the superhero powers of the Avengers in a really interesting way. The characters interact in unexpected yet exciting scenarios.
One great HP Avengers fanfic is 'The Avengers at Hogwarts'. It has an interesting plot where the Avengers are somehow transported to the wizarding world. They have to adapt to the magic there while also dealing with the threats in Hogwarts. Another one could be 'Avengers and the Hogwarts Students United'. In this, the Avengers team up with the students to fight against a common enemy that poses a danger to both the Muggle and wizarding worlds.
Thor and Hagrid are also frequently paired. Thor's god - like status and Hagrid's love for magical creatures create a unique bond. They might go on adventures together in the Forbidden Forest or something. And of course, Captain America and Dumbledore. Their leadership qualities are often compared and they can work together to lead the combined forces of the Avengers and the Hogwarts students against the bad guys in the fanfic world.
Maybe in the fanfic, Batman's rogues gallery somehow teams up with some of the Avengers' villains. This forces Batman and the Avengers to work together. Batman could introduce his unique gadgets and combat style to the Avengers, while they could show him their superpowers up close. For example, Iron Man could be intrigued by Batman's utility belt and try to create his own version of some of the gadgets.
A good plot could involve a villain from the Homestuck universe creating chaos in the Avengers' world. The Homestuck characters come to help, but there are misunderstandings at first between them and the Avengers. However, as they start to understand each other's powers and motives, they form a strong alliance to defeat the villain.
One common theme is the clash of different cultures. Loki comes from a different mythological background, and when his wife enters the HP world, there's a lot of cultural differences to deal with. For example, the magic in Loki's world might be different from that in Hogwarts.
Some Harry Potter or Game of Thrones - themed forums might also be a good source. There are often threads dedicated to fanfiction, and members may share their own HP got crossover works or recommend ones they've read. For example, the Leaky Cauldron forum for Harry Potter fans or some Game of Thrones fan communities on Reddit.