A possible plot is that the self - inserted character has to deal with the Omnitrix malfunctioning. This could lead to unexpected and sometimes comical transformations. They might transform into a really weak alien in the middle of a battle or into an alien that is completely inappropriate for the situation, like a tiny alien when they need to be strong. As they try to fix the Omnitrix, they learn more about its inner workings.
Well, the self - inserted character could be from a different dimension where the Omnitrix is more powerful or has different aliens. They get transported to the normal Omnitrix universe and have to adapt. They could introduce new techniques for using the Omnitrix that the other characters haven't thought of. Maybe they have a special bond with one of the aliens in the Omnitrix that no one else does, and this helps them in their adventures.
You could insert yourself as a human knight. Picture this: you are part of the Stormwind army, and you get involved in the fight against the orcs. During a battle, you find a mysterious artifact that gives you special abilities. This leads you on a quest to find out more about the artifact's origin and how it can be used to save humanity from various threats like the Scourge or the demons.
Your self - insert could be a transfer student from another kingdom with a completely different fighting style. This would lead to interesting interactions with the main characters as they learn from each other. They might introduce new weapons or combat techniques that the others haven't seen before.
One idea could be that Hela, as the self - inserted character, tries to reform the Avengers from within. She could use her unique powers and knowledge of Asgardian lore to help them face a new, powerful enemy. Maybe she starts off as a suspicious figure but gradually gains their trust through her heroic deeds.
A good plot for Highschool DxD self - insert fanfiction might be that the self - insert character is actually a reincarnation of an ancient and powerful being. They start off not knowing this, but as the story progresses, they gradually unlock their past memories and powers. This could lead to them having to make choices between their new life in the Highschool DxD world and their old responsibilities from their past life.
One idea could be that you insert yourself as a skilled navigator who joins the Straw Hat crew and forms a special bond with Nami. You could help her create new and more accurate maps, and together face the challenges of navigating through uncharted waters. Another plot could involve you having a special power related to weather control, which complements Nami's own abilities with the Clima - Tact. You work together to protect the crew from powerful storms and enemies that use weather - based attacks.
One idea could be inserting yourself as a new recruit in the Howling Commandos. You could have a special skill, like being an expert in decoding enemy messages. Then, you get to interact with Captain America and the team, facing challenges together and forging strong friendships. Another plot could be that you are a scientist in the same era as Steve Rogers. You accidentally discover a new element that could enhance the super - soldier serum. This draws the attention of both Captain America and the bad guys, leading to a race to protect or steal your discovery.
One idea could be inserting yourself as a new student with a unique cooking style from a different culture. For example, you could introduce a fusion of Scandinavian and Japanese cuisine that wows the judges and students at Totsuki. Another plot could involve using self - inserted character to revive an old family recipe that has been forgotten and make it popular again in the cut - throat world of Totsuki.
One idea could be that your self - insert character is a new student at the Yokai Academy. They initially struggle to fit in among the various supernatural beings but gradually discover a unique power within themselves that helps them gain respect. For example, they might have the ability to communicate with spirits that others can't, which becomes useful in solving a mystery at the school.
Another plot could involve the self - insert becoming a sort of mentor to the younger Sailor Scouts. Maybe they have knowledge from their own world about magic and combat that they can pass on. They could help Sailor Moon, in particular, gain more confidence in her leadership role. This would create a new dynamic within the group and lead to different story arcs as they face challenges together.
One idea could be inserting yourself as a character who has a unique skill like being a master tracker. You could help the group find food and supplies more easily. Another could be a character with medical knowledge who tries to prevent the spread of diseases within the group.