A really cool plot could be that they turn into humans and then try to blend into high school as normal students. They have to deal with typical high - school drama like fitting in, making friends, and dealing with bullies, all while hiding their true identities from everyone around them.
The Cullens themselves are the main characters. There's Carlisle, the patriarch of the family, who as a human now has to use his medical knowledge in a new way. Esme, who might be exploring her newfound humanity with a sense of wonder. And then there are the younger Cullens like Edward, Bella (if she's involved in this particular fanfiction), and the others, each having their own unique experiences and reactions to becoming human.
One possible plot could be Nick and Judy adjusting to human society. They might struggle with new social norms and expectations. For example, Nick, who was used to being a sly fox in the animal world, now has to learn to be more straightforward as a human. Another plot could involve their relationship evolving in a different way as humans. Maybe they face new challenges in their friendship or even start to develop romantic feelings in a more human - like context.
One interesting plot could be Bella developing a new power while living with the Cullens. For example, she might gain the ability to communicate with animals like some of the other vampires. This would add a new dynamic to her relationship with the Cullens and also pose new challenges and adventures as they try to keep it a secret from the outside world.
One interesting plot could be a magical duel between Harry Potter and one of the Cullens. Maybe they meet in a special dimension where magic from both universes co - exist. Harry uses his spells like Expelliarmus while the Cullen uses their vampire - related powers.
Well, a major concept is the power dynamics. Mobians may have different power levels compared to humans. When a human turns into a mobian, they might gain or lose certain powers. This can lead to all sorts of plot developments, like having to deal with new enemies or allies. And there's the concept of appearance change. How do they look now? Do they like their new look? And how do others react to their new mobian appearance?
One interesting idea could be the exploration of the crystal gems' newfound human emotions. For example, how they deal with things like vulnerability and mortality. Another could be their interaction with the human world in a more 'human' way, like going to school or having a regular job.
There could be a plot where a human is cursed by an evil witch, and a good witch decides to help the human break the curse. Along the way, they form a deep bond. The human learns about the witch's world, and the witch learns about human emotions like love and friendship, which in the end, is the key to breaking the curse.
A possible plot could also be a time - travel - like scenario within the fanfiction. Wheatley and Chell find themselves sent back to an earlier era of the Aperture Science facility. They have to figure out how to get back to their own time while also dealing with the different technology and perhaps even different versions of the characters they knew.
In some fanfiction of this kind, the monkeys might kidnap a human because they think the human is a key to unlocking a hidden treasure or ancient knowledge. They see the human as having some unique quality like intelligence or intuition that they lack. So they take the human to their secret lair in the jungle and try to communicate with them to get what they want.
One interesting plot could be Izuku developing new and unique powers that no one has ever seen before. For example, he might gain the ability to manipulate time on a small scale, which would add a whole new dimension to his battles and his journey to become the strongest.