One idea could be that Hulk somehow gets transported into the wizarding world of Harry Potter. Maybe a magical experiment gone wrong by a Hogwarts student creates a portal that sucks Hulk in. He could then cause chaos as he's not used to the magic and strange creatures there.
Harry Potter would probably be initially cautious around She - Hulk. He's used to magic and magical creatures, but She - Hulk is a whole new level of different. However, as he gets to know her, he would respect her strength and her sense of justice. She - Hulk, on the other hand, would be amazed by the magic in the wizarding world. She might try to learn some spells and would be very protective of Harry and his friends, just like she is in her own world.
In a fanfic, it could be that the magic in the Harry Potter world has an unexpected effect on Hulk. For instance, the magic might make Hulk's transformations more controllable, or it could give him the ability to communicate better. And in return, Hulk's super strength and durability could be used to protect Hogwarts from various threats, like a giant dragon attack or an invasion of dark creatures. This way, both elements of the two universes blend well and create an exciting story.
One idea could be that the Hulk somehow gets transported to the wizarding world. Maybe a magical experiment gone wrong by a Hogwarts student creates a portal. The Hulk's brute strength would be a shock to the wizards and witches. He could end up causing chaos in Hogwarts, knocking down walls and scaring students. Wizards would try to use spells on him, but his strength might make him resistant at first.
One way to combine them could be in an alternate universe fanfic. Maybe Harry Potter discovers a magical aluminum alloy that has some strange properties. And She - Hulk could be brought into this world through a magical accident. For example, a spell gone wrong could transport her to the wizarding world where Harry Potter is. Then they could interact, with She - Hulk's strength and Harry's magic creating interesting scenarios. The aluminum could be part of some new magical item or contraption that they have to deal with.
A third plot might be that a spell gone wrong in the wizarding world creates a rift that pulls She - Hulk into it. She then has to find a way back home while also getting involved in the ongoing struggle between the good wizards led by Harry Potter and the dark forces. Along the way, she could use her legal knowledge (since she's also a lawyer) to help resolve some disputes within the wizarding community that are related to new magical laws.
A 'Harry Potter is the Hulk fanfiction' could be a very interesting take on both universes. Imagine Harry being in Hogwarts but having the Hulk's abilities. He might accidentally break things around the castle when he gets angry. His professors would be puzzled on how to handle this new situation. And in battles, he could be a one - man army. He could jump great distances like the Hulk and at the same time use his Patronus charm. It would be a story full of unexpected twists and turns as he tries to balance his two very different identities and powers.
Well, it could be that Harry Potter somehow gets the powers of the Hulk. Maybe a spell gone wrong during a Defense Against the Dark Arts class that combines his magic with some strange gamma - ray - like magic, and he starts to transform into a green - skinned, super - strong being. He then has to deal with both the wizarding world's problems and his newfound Hulk - like powers.
A common theme is the clash of two different worlds. The magical world of Harry Potter and the super - powered world of the Hulk. This often leads to misunderstandings and comical situations as the characters from each world try to figure out the other.
One idea could be that She - Hulk, in her human form, discovers she has magical abilities and gets a letter from Hogwarts. She then has to navigate the wizarding world while also dealing with her Hulk - like powers. It would be interesting to see how she interacts with the magical creatures and students at Hogwarts, like when she meets Hagrid or has a duel with Draco Malfoy.