Well, how about this? Cinderella is actually an ancestor of Marinette. And Marinette discovers an old diary of Cinderella's that has some hidden secrets about the Miraculous. It seems that Cinderella had a connection to the Miraculous long ago. This discovery leads to a new adventure where Ladybug has to follow the clues in the diary to find a lost Miraculous that could be very powerful. Along the way, she meets characters who are like the ones in Cinderella's story, but with a Miraculous Ladybug twist.
A plot idea could be that a villain creates a prosthetic - like device that can steal the powers of the Miraculous holders. Ladybug and Chat Noir have to figure out how to stop this device and also deal with the fact that some of their friends or allies might be affected by it. Or perhaps there's a character who has always been self - conscious about their prosthetic, but when they get a Miraculous, they learn to embrace it and see it as a strength. They could inspire other characters with disabilities in the story.
One idea could be to create a Ladybug costume that is tattered and covered in fake spiderwebs to give it a spooky Halloween twist. You could also add some fake blood splatters to make it look like Ladybug has been in a battle. Another option is to make a dark version of the costume, with a black instead of red suit and purple spots.
One creative idea is a crossover with the Jurassic Park world. Imagine Ladybug and Cat Noir having to fight dinosaurs while still maintaining their secret identities. Another is a crossover with the Alice in Wonderland world. The wacky and strange nature of Wonderland would make for an interesting backdrop for the Miraculous heroes.
One idea could be a story where the Peacock Miraculous has a unique malfunction that causes it to create unexpected akumas. For example, instead of creating the usual villains, it creates akumas that have the power to spread positive emotions but in a chaotic way that still disrupts Paris. Another idea is a fanfiction where the holder of the Peacock Miraculous has to team up with Ladybug and Chat Noir to fight against an ancient evil that is specifically drawn to the power of the Peacock. This could involve exploring the history of the Miraculous and its connection to this new threat.
One idea could be that Ladybug and Chat Noir are sent to space on a mission to stop an alien villain who is stealing energy from planets. They have to adapt to zero - gravity combat and use their powers in new ways. For example, Ladybug's yo - yo could be used to grapple onto spaceships.
A plot could involve the whole gang from Miraculous Ladybug going camping together. Marinette could be worried about Tikki being discovered in the wild. Meanwhile, Adrien, as Chat Noir, tries to impress Marinette. And during the camping trip, there's a mystery about a strange light in the forest that turns out to be related to an ancient Miraculous. So they all have to work together to figure it out.
A plot idea could be that the Bubbler becomes an anti - hero. He realizes that his way of trapping people in bubbles was wrong, but he still wants to use his powers for good. So he starts using his bubbles to protect people from other villains, like creating a bubble shield around the city when an especially dangerous akuma attacks.
One idea could be that Ladybug and Chat Noir's Miraculous are somehow linked to Pokemon powers. For example, Ladybug's yo - yo could have the ability to capture and communicate with certain Pokemon. Another could be that Hawk Moth is trying to use Pokemon to take over Paris. And perhaps Marinette discovers she has a special connection to a rare and powerful Pokemon that helps her in her fight against evil.
Well, you could write a fanfic where Ladybug and Chat Noir get transported to an alternate universe. In this universe, their roles are reversed, and they have to figure out how to get back to their own world while dealing with the differences. Also, a plot could revolve around a Miraculous that has been lost for centuries suddenly resurfacing, and all the chaos and mystery that comes with it. Maybe a story about Ladybug having to deal with a personal crisis that affects her superhero duties, like losing her confidence after a major defeat.
One idea could be that the Reverser's powers are amplified and he starts reversing not just individual actions but entire relationships in Paris. So, Marinette and Adrien's unspoken bond is reversed, making them avoid each other at all costs. Another could be that the Reverser targets Ladybug's and Chat Noir's memories of their superhero identities, causing chaos as they try to figure out who they are again while still having to fight akumas. A third idea is that the Reverser somehow manages to reverse the concept of good and evil in Paris, making the akumas seem like the heroes and the heroes like the villains, and Ladybug and Chat Noir have to find a way to reverse it back.