Well, a great plot could be that the next - gen demigods discover a hidden part of the Underworld that was sealed off long ago. In this new area, there are strange and powerful entities that they have to either befriend or defeat. Also, they could be on a quest to rescue a group of young demigods who were kidnapped by a cult that worships an ancient and evil god. It would be full of action as they fight their way through the cult's lair and face all kinds of traps.
One idea could be the children of the original demigods going on a quest to find a new, powerful artifact that's been lost. For example, a magical shield that once belonged to a forgotten hero. Another plot could involve them facing a new type of monster that's a combination of different mythological beasts, like a chimera with the powers of a manticore. They might also have to deal with internal camp politics as the new generation has different ideas about how to run Camp Half - Blood compared to their parents.
A cool plot for next generation Percy Jackson fanfiction would be that a prophecy predicts the destruction of all demigod camps unless the new generation can find a way to unite all the different pantheons. So, the kids of Percy and his friends have to travel around the world, visiting different camps of various mythologies like Norse, Egyptian, and Chinese demigod camps. Along the way, they face cultural clashes, language barriers, and of course, the usual array of mythical monsters trying to stop them from achieving their goal.
Another plot could revolve around a time - travel aspect in the Twilight Next Generation fanfiction. A young character accidentally travels back in time to when their parents first met and starts to interfere. This could lead to all sorts of changes in the timeline and force them to find a way to fix it before they cease to exist in their current form.
One idea could be the next generation facing a new, more powerful enemy that combines the powers of all the previous villains. They'd have to learn from their parents' stories and develop new skills to defeat it.
A plot idea could be that the next generation of Miraculous holders has to team up with some of the old villains' descendants who are now on their side. They have to overcome the prejudice from the public who don't trust them. Together, they work to stop a new evil that is threatening to destroy the balance between the Miraculous powers and the normal world.
One idea could be about a new type of Pokemon that emerges in the next generation. Maybe it's a fusion of two existing types due to some strange environmental phenomenon. Another could be a story where the main character is a descendant of a famous Pokemon trainer from the previous generations and has to live up to their legacy while facing new challenges in the Pokemon world.
Another plot could involve the next - generation Avengers having to prove themselves to the world. The public is skeptical of them at first, thinking they can't live up to their parents' legacies. So they take on a mission to save a major city from a powerful alien invasion, and in the process, they gain the public's trust.
Another plot could revolve around the relationships between the children of the original RWBY characters. For example, if Ruby's daughter has a different view on hunting Grimm compared to her mother. It could lead to internal conflicts within the new team and also show how the world has changed since the first generation's time. There could be political aspects too, like new laws regarding Huntsmen and Huntresses that they have to navigate.
One idea could be focusing on the children of the Straw Hat crew. For example, Luffy's son might inherit his rubber abilities but also have a unique power of his own. He could embark on a journey to find a new One Piece that is different from what his father was after, perhaps something more related to the forgotten history of the world. Another plot could be about the next generation of pirates from other crews teaming up with the Straw Hat descendants to face a new, powerful enemy that is even more menacing than the World Government in the original series.
Perhaps the story could focus on a group of students who are trying to expose the identity of the new Gossip Girl, just like the old crew did. But this time, there are more secrets and twists involved. For example, some of the characters might be related to the original Gossip Girl, which adds an extra layer of mystery.
One idea could be Boruto going on a solo mission to a far - off land that has a unique chakra - based mystery. Maybe there's an ancient power there that's starting to awaken and Boruto has to figure out how to stop it from being misused.
One idea could be the new generation dealing with a secret society within the school that controls the social hierarchy, just like the original Gossip Girl. Another could be a love triangle between the children of the main characters from the original series, with one falling for an outsider who brings new drama. Maybe there could also be a mystery around a long - lost relative of one of the main families that resurfaces and shakes up the Upper East Side.