Well, a plot could involve the child of the emperor being trained in secret by a powerful mage. This mage could be using the child for their own purposes, but the child gradually realizes this and has to break free. Also, the child could be in a love triangle with a noble from another kingdom and a commoner within their own empire. They have to choose between love and duty.
One idea could be the child of the emperor having to navigate the complex politics of the court while hiding their true identity. Another could be the character's journey to discover their heritage and claim their rightful place in the empire. Maybe the child is exiled and has to fight their way back to power.
One idea could be exploring the child emperor's relationships with his advisors. Maybe he has a young, brilliant advisor who becomes his best friend and they work together to improve the kingdom. Another idea is to focus on the child emperor's education, like how he learns about politics, war strategies, and diplomacy from different tutors.
One idea could be exploring the character's backstory more deeply. For example, how they came to be in the situation they are in the original story. Another could be a crossover with another related fandom, bringing in new elements and characters.
One idea could be Naruto as an emperor having to deal with political intrigue within the ninja villages. He might face challenges from rival clans who don't want to accept his new authority.
The plot could involve the child being sought after by various ninja clans who want to use the power of the Kyuubi within the child for their own purposes. The child, with Naruto's teachings, resists and tries to find a way to use the power for the good of the village. Maybe the child discovers a new form of chakra control that combines Naruto's Uzumaki heritage and the Kyuubi's power.
A great plot idea is that the child has a special connection to the sea, like Percy, but also has Annabeth's wisdom. So they use this combination to solve a mystery that has been plaguing Camp Half - Blood for years. For example, the mystery of why some demigods' powers are fading. Another could be that the child gets sent back in time and has to interact with their parents when they were younger. This could create some really interesting situations and challenges for the child.
One idea could be that Harry discovers he has a unique magical ability that even Dumbledore doesn't know about. This ability could be related to his connection with the very essence of magic. For example, he might be able to communicate with magical creatures in a way no one else can, which leads him to uncover secrets about Hogwarts' past.
One idea could be exploring how the child of prophecy discovers their true power earlier than in the original Naruto story. Maybe they start to unlock unique jutsu that no one has ever seen before, which changes the course of the ninja world.
A great plot idea could be that Child Emperor discovers a way to time - travel. He decides to go back in time to learn from the greatest minds in history to further his inventions. But when he gets back to his own time, he realizes that his actions in the past have caused some unforeseen consequences, like a new villain emerging who has knowledge of ancient and powerful technology. He then has to enlist the help of other heroes to fix the mess.
Perhaps the child OC is on a quest to find a missing family member in the post - apocalyptic world of The Walking Dead. They could encounter various groups along the way, some friendly and some not, which would create a lot of tension and character development.
One idea could be exploring the relationship between the new character, the Demons Child, and the existing Hogwarts students. Maybe the child has unique powers that both intrigue and frighten others.