One popular trope is the 'alternate universe' where the story takes place in a different setting than the original books. For example, a modern muggle world with a hidden wizarding society. Another is the 'time - travel' trope, which allows characters to go back in time and change events. And the 'found family' trope is also common, where characters form deep bonds outside of their biological families.
In Si Harry Potter fanfiction, a common trope is the 'teacher - student relationship' in a different context than in the original. Maybe a student teaching a teacher something new about magic. The 'prophecy' trope is also seen often, where a new prophecy drives the plot. And the 'redemption' trope, where a previously 'bad' character gets a chance to turn good.
One popular trope is the 'alternate universe' where the story takes place in a different setting or with different rules from the original series. For example, a world where Voldemort won. Another is the 'character rewrite' where a character's personality or backstory is changed. And the 'romantic pairing' trope, like Hermione with Draco, which explores relationships that weren't in the original books.
One popular trope is the 'coming - out' story. This could involve a character like Harry Potter himself realizing and coming to terms with his bisexuality. It often includes the character's internal struggle, as well as how their friends and the wizarding world around them react.
One popular trope is the 'fish out of water' situation where the main character, often a self - insert or an OC, finds themselves in the middle of a harem of Harry Potter characters. Another is the 'enemies to lovers' within the harem, where some of the characters initially dislike the main character but then fall for them. Also, the 'power - up' trope is common, where the main character gains new magical abilities or knowledge through their interactions with the harem members.
One popular trope is the 'enemies - to - lovers' where characters who initially dislike each other, like Draco and Hermione, fall in love. Another is the 'forbidden love' trope, for example, a love between a Muggle - born and a pure - blood in a world with so many class differences in the wizarding world. And of course, there's the 'soulmate' trope where two characters are fated to be together.
A common trope is power - related. In Harry Potter and Marvel fanfiction, you often see characters either sharing or comparing their powers. For instance, how would Captain America's physical abilities stack up against a wizard's magical skills? Also, the 'found family' trope is there. Characters from both universes coming together to form a new family unit, like some Avengers joining forces with the Hogwarts crew.
One popular trope is the 'crossover' where characters from Charmed and Harry Potter universes interact. For example, the Halliwell sisters might meet Harry, Hermione and Ron. Another is the 'power transfer' trope, like a Charmed one getting some magical ability from the Harry Potter world or vice versa. And the 'hidden relation' trope is also seen, such as a character from one universe being related to a character in the other in some unexpected way.
A common trope is the 'alternate universe' idea. In these fanfictions, the wizarding world could have a completely different social structure or history. For instance, if the Death Eaters had won the war before Harry started at Hogwarts. Also, the 'romantic pairings different from the canon' trope is popular. Fans like to explore relationships like Hermione with Draco or Harry with Luna that are not the main focus in the original books.
One popular SI OC Harry Potter fanfiction is 'The Changeling'. It has an interesting take on a self - inserted original character in the wizarding world. The story follows the OC as they navigate Hogwarts and deal with the challenges and mysteries there.
One popular trope is the 'what if' scenarios. For example, in Game of Thrones fanfiction, 'What if Ned Stark didn't lose his head?' In Harry Potter, it could be 'What if Harry was sorted into Slytherin?' Another is the crossover trope, where characters from both universes meet. This can lead to really interesting interactions as the magic systems and cultures of both worlds collide. And of course, there are the fix - it fics, where fans rewrite parts of the story they didn't like. For instance, in Game of Thrones, giving a more satisfying end to certain characters' arcs.
A common trope is the 'power imbalance' which gets resolved over time. Since Thor is a powerful god and Harry is a powerful wizard, initially there might be a struggle for dominance or understanding. And then there's the 'shared destiny' trope. Maybe they are fated to save both the Asgardian and wizarding worlds together. This makes for an interesting dynamic in the fanfiction.