Another plot could involve the other Avengers having to protect Steve in his de - aged state. They would be extra cautious as he is now more vulnerable physically. Maybe they have to keep his identity a secret from the public too, which adds to the drama.
One interesting plot could be Steve adjusting to the new, younger body while still having the mind of an older hero. He might struggle with modern technology even more than before, leading to some comical situations. For example, trying to figure out a smartphone or a new type of vehicle.
In some de - aged Avengers fanfiction, the team's relationships are explored in a new light. When they are de - aged, they might form different bonds. For instance, Thor as a youngling could form a closer friendship with a de - aged Black Widow. They might rely on each other in ways they didn't before, as they are both out of their element in their de - aged forms and have to find new ways to trust and support one another.
With Natasha, she might become more protective of Steve. In his de - aged state, she could see him as someone who needs more safeguarding, and their friendship could deepen as she shares her own experiences to help him adapt.
Another plot might involve the Avengers trying to figure out how to deal with de - aged Tony and Loki. They could be worried about Loki's intentions since he's usually a villain, but at the same time, they have to take care of a child - like Tony. This creates a lot of comical and tense situations.
One interesting plot could be Peter Parker de - aged to a child and having to navigate his old life with his current knowledge. For example, he might struggle to hide his superhero identity from his younger self's friends and family. Another plot could involve him going back to school as a child while still having his adult - level intelligence, which could lead to some comical and also poignant situations as he tries to fit in with kids his age.
Fanfiction.net is also a good place to look. There are numerous writers on there who might have come up with interesting de - aged Avengers stories. Browse through the Avengers category and look for tags related to de - aging.
A possible plot is that when Naruto is de - aged, he forgets some of his later - learned ninja techniques. So he has to start from scratch and relearn them in a different way. This could lead to him developing new and improved versions of those techniques. Also, the de - aging could be part of a villain's plot. Naruto then has to figure out how to reverse it while also dealing with the chaos that his sudden change in age has caused in the village, like how his friends now have to protect him instead of the other way around.
One possible plotline could be that the Avengers are under the influence of a mind - controlling villain. They turn on Steve because he's seen as a threat to the villain's plan at that moment. Another could be a misunderstanding. For example, false evidence is planted that makes the Avengers believe Steve has betrayed them, so they accidentally hurt him while trying to stop what they think is his betrayal.
One interesting plot twist could be that the de - aged Harry has some hidden memories of the future that help him in the tournament in unexpected ways. For example, he might remember a particular spell that an opponent will use and be able to counter it easily.
Well, a possible plot could involve Harry being de - aged due to a spell gone wrong in one of Snape's potions experiments. Severus then has to take on the role of a caretaker. He could start to see Harry in a new light, not just as James Potter's son. And Harry, in his de - aged state, might be more open and trusting towards Severus, leading to some heart - warming moments between them as Severus teaches Harry some advanced magic concepts in a more gentle way than he would with an older Harry.
One interesting story could be where Jim is de - aged and has to navigate the ship's politics all over again from a new perspective. He might face challenges as the crew initially doesn't take him seriously because of his young appearance but he gradually proves himself.