A new villain could have a weapon that specifically targets Ladybug's powers. When she tries to use her yo - yo or her powers of creation, it backfires and causes her harm. This would force her to rely on her wits and Chat Noir more than ever. They would need to find a way to neutralize the weapon and heal Ladybug.
Well, when Ladybug gets hurt in fanfiction, it can change the whole dynamic of the story. Her injury could be a turning point. Maybe she loses her confidence for a while. This could make her more vulnerable, and the other characters might see a different side of her. It could also lead to some self - discovery as she has to deal with not being at her best all the time.
Chat Noir would be really worried. He might blame himself for not being there to protect her. He would probably stay by her side until she recovers. And Marinette's friends like Alya would also be concerned. They might try to keep her identity a secret while also taking care of her as Marinette.
In an akumatized Ladybug fanfiction, the akuma might enhance her powers in unexpected ways. For example, her Lucky Charm could become a more powerful and unpredictable object. Her akumatized form might also have a darker and more menacing look, perhaps with a more aggressive fighting style. Writers could explore how the heroes and villains interact with this changed Ladybug.
Maybe in the fanfiction, the Quantum Kids are from a parallel dimension where the Miraculous powers are based on quantum physics. When they meet Ladybug and Cat Noir, they initially cause some chaos as their powers interact in unexpected ways. But eventually, they learn to combine their powers to defeat an ancient evil that threatens both their worlds. For example, the Quantum Kids could help Ladybug and Cat Noir access a different plane of existence to retrieve a powerful Miraculous that was lost there.
In this fanfiction, the Quantum Kids - let's say there are four of them named Kira, Kai, Mia, and Leo - are the central characters from their own realm. They have powers like quantum shifting and energy projection. Ladybug and Cat Noir are the main heroes from their world. Then, there could be a new character, a scientist who has some knowledge about both quantum mechanics and the Miraculous. This character could help bridge the gap between the two groups and be an important part of the story as they all work together to face threats.