The 'unlikely allies' trope is often used. Given their very different backgrounds, fem Harry Potter and Bruce Banner make for an unlikely pair. But in fanfiction, they often end up working together towards a common goal. There's also the 'culture clash' trope as the magical and scientific cultures they come from are so different. This leads to some really interesting interactions and storylines.
I really liked a fanfic where fem Harry Potter accidentally travels to Bruce Banner's world. It shows how she tries to adapt to this new world full of science and technology, which is so different from the magical world she's used to. And Bruce Banner is intrigued by her magic. It's a great exploration of two very different characters coming together.
Fem Harry Potter might be initially cautious around Bruce Banner, especially if she witnesses his transformation into the Hulk. She could use her magic to try and calm him down when he's in a Hulk - rage. Bruce, on the other hand, would be fascinated by Harry's magic. He might study it scientifically, trying to understand the principles behind it.
Maybe Fem Harry Potter is on a quest to find a magical object that has found its way into the Marvel world. Bruce Banner, in his Hulk form, initially scares her but then they realize they can help each other. The Hulk's strength could be useful in protecting Harry from physical threats while she uses her magic to protect Banner from magical ones.
One popular trope is the 'fish out of water' situation. For example, Bruce Wayne finding himself in the magical world of Harry Potter and having to adapt to the new rules and magic. It creates a lot of comical and interesting situations.
Perhaps Bruce Banner adopts Harry Potter after the events at Hogwarts. He takes Harry to the world of science, showing him things like advanced laboratories and scientific research. Harry, in turn, shows Bruce the wonders of magic. Their bond grows as they learn from each other, and together they face new threats that combine elements of both the magical and scientific worlds.
One popular trope is the 'fish out of water' scenario. A fem Harry Potter in the realm of Hades would be quite out of place. She'd have to adapt to the dark and often unforgiving world of Hades. Another is the 'powerful outsider' trope. Given Harry's magical abilities, she'd be a force to be reckoned with in Hades' domain. And the 'romantic entanglement' trope is also common, perhaps a relationship between fem Harry and Hades or one of his minions, adding a layer of drama and passion to the story.
In fanfiction, Bruce Banner could save Harry Potter through his scientific knowledge as well as the Hulk's powers. Maybe there's a situation where a magical curse is spreading uncontrollably. Bruce, in his normal state, could analyze the curse using his scientific expertise and figure out a way to stop it. And if there are any physical manifestations of the curse that need to be dealt with, the Hulk could step in and use his strength to destroy or contain them. This would show a great combination of the scientific and magical elements in the story.
In Harry Potter fanfiction, a common trope with Fem Blaise is the 'hidden - power' trope. This means that she has some sort of hidden magical ability that is only revealed as the story progresses. It could be something related to ancient magic or a unique way of using spells. Also, the 'outsider - within - Slytherin' trope is quite popular. Despite being in Slytherin, she may not fit in completely because she has different values or beliefs. This can lead to her having to navigate complex social situations within her own house while also forming connections outside of it.
In fem Harry Potter and Sailor Moon fanfiction, a common trope is the friendship - building aspect. The characters from both series have to learn to trust and work together. This often involves some initial misunderstandings and then a deepening of their relationships. Also, the 'hidden identity' trope is quite popular. Maybe fem Harry has to keep her wizarding identity a secret in the Sailor Moon world or vice versa.
A common trope is the 'romantic entanglement' trope. Writers often pair the fem Harry Potter with various characters from Game of Thrones. It could be with Jon Snow, creating a story of two outcasts coming together. Or she might be paired with Tyrion Lannister, leading to an interesting dynamic of a powerful magical being and a clever, but often underestimated, man. There's also the 'mentor - mentee' trope where she either mentors someone in Westeros about magic or is mentored by someone about the ways of Westeros.