A great plot could involve the inmates of the asylum unknowingly being experimented on by a secret group related to the Twilight lore. They start to develop strange powers or behaviors similar to the supernatural beings in Twilight.
Perhaps the asylum is actually a cover - up for a place where Twilight's outcasts, like those vampires who don't follow the Cullen's code, are hidden. A fanfic could revolve around a human who discovers this secret within the asylum walls.
One idea could be a story from the perspective of a minor character in the Twilight series, like a werewolf from a different pack who has an encounter with the Cullens. It could explore how they view the vampires and their relationships in Forks.
One idea could be a new vampire character arriving in Forks who has a unique power that disrupts the existing power dynamics between the Cullens and other vampires. For example, this new vampire might be able to manipulate time briefly, which could lead to some really interesting situations like preventing certain events from the original 'Twilight' series from happening or changing the way characters interact.
Another plot could be a time - travel twist. A character accidentally travels back in time and has to navigate the world of Nightfall Twilight in a different era. They might meet younger versions of the main characters and change the future in unexpected ways.
One possible plot idea could be exploring a different backstory for one of the main characters. For example, giving Bella a more complex family history that ties into the vampire - werewolf lore in new ways. Another idea might be a time - travel plot where a character goes back to change an event in the Twilight series, which then has a ripple effect on all the relationships. Or perhaps a story where a new supernatural creature enters Forks and disrupts the existing balance between vampires and werewolves.
One idea could be exploring the backstories of the characters in more depth. For example, delving into their past relationships, traumas, or what led them to be in the situation during the Emerald Twilight. Another could be a 'what if' scenario, like what if a different character had made a crucial decision during that time. Maybe a fanfic where a minor character steps up and changes the course of events.
One idea could be a story about a new wolf joining the pack and having to prove their worth. Maybe they have a unique ability that the pack initially doubts but later comes to rely on.
A cool plot for a Harry Potter Twilight fanfic could be a competition. The wizards from Harry Potter and the vampires and werewolves from Twilight compete in a series of challenges. These challenges could test both magic and the unique abilities of the Twilight characters. Or perhaps a love triangle between a Harry Potter character, a Twilight vampire, and a Twilight werewolf. It would be interesting to see how the different cultures and powers interact in matters of the heart.
One idea could be exploring uncharted territories in the 'beyond duty' world. Maybe the characters face new and strange creatures that test their limits.
One idea could be exploring the backstories of the characters in the 'hopeless kingdom' within the Twilight universe. Maybe a character who was once a normal human in Forks but got dragged into the chaos of the hopeless kingdom. Another could be a love triangle between a vampire, a werewolf, and a human in this new and desolate setting.
One idea could be that Trixie and Twilight Sparkle team up to solve a mystery in Equestria. Maybe a powerful magical artifact has gone missing and their combined knowledge of magic is needed to find it.