One idea could be Carapace getting a new power upgrade and having to learn to control it while facing a powerful new villain. Maybe he teams up with a new Miraculous holder.
Another interesting plot could be that Carapace gets transported to an alternate dimension where the rules of the Miraculous are different. He has to figure out how to get back while also dealing with the strange versions of his friends and enemies in that dimension.
A plot could revolve around Carapace's civilian life. For example, Nino could be struggling with a school project, and his experience as Carapace gives him the confidence and problem - solving skills to overcome it. And then he has to use his superhero skills to stop a minor akuma attack at school.
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 during Halloween, the Miraculous holders have to deal with akumas that are inspired by classic horror movie monsters. For example, an akuma that turns into a vampire - like creature, making people fall under its spell and causing chaos in the city. Another plot could be a Halloween party where the villains try to steal the Miraculous in disguise, adding an element of mystery and danger.
One idea could be that the fox Miraculous has some unique powers that are not fully explored in the original. For example, it can create illusions not just of objects but also of emotions, which the fox - themed hero uses to calm down akumatized villains.
A plot where there is an international Miraculous team-up. Heroes from different countries with their own Miraculous come together to face a global threat. They have different fighting styles and powers, and it's a challenge for them to work together against a common enemy in this showdown.
One idea could be a crossover where the Miraculous heroes and Ben 10 team up to fight a common enemy. Maybe an alien villain that is immune to the powers of the Miraculous but Ben's alien forms can counter. Another could be a situation where Ladybug's Lucky Charm combines with one of Ben's alien gadgets to create a super - weapon. And a third could be a story where Ben gets akumatized and the Miraculous heroes have to figure out how to save him without using brute force as his alien forms are very powerful.
One idea could be Multimouse getting lost in an alternate dimension where the rules of the Miraculous are different. She has to figure out how to use her powers in new ways to get back home.
One idea could be that the Miraculous Phoenix has the power to heal not only physical wounds but also emotional traumas. The story could follow a character who is deeply scarred by past events and is chosen by the Phoenix Miraculous. As they learn to use its powers, they gradually heal themselves and those around them.
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.
One idea could be that the thief has a secret noble cause. Maybe they steal to return precious items to their rightful owners who were wronged in the past. For example, an artifact was stolen from a family long ago, and the thief is trying to make things right.
One idea could be that Zombizou actually has a hidden power within her zombie state that she can transfer to Ladybug or Chat Noir to help them defeat a new super - villain. For example, she might be able to make them invisible to the villain's special powers for a short time.