Well, in some 'time travel to ww2 fanfiction', a character might go back in time and end up changing the course of a major battle. For example, they could provide crucial intelligence that was previously unknown. Or perhaps a time traveler finds themselves in the middle of a resistance movement, helping to smuggle important people or documents. Also, there could be a story where the time traveler has to deal with the moral dilemmas of interfering in history, while still trying to make a positive impact.
One interesting plot could be a modern person traveling back to WW2 and using their knowledge of future technology to help the Allies in a covert way, like improving communication systems. Another could be a time traveler trying to prevent a particular tragic event during the war, such as the bombing of a certain city. And there might be a plot where the time traveler has to adapt to the harsh wartime conditions and forms unexpected friendships with soldiers on the front line.
One idea could be a soldier from WW1 suddenly finding himself in the middle of a WW2 battle. He might use his old - fashioned combat skills in a new and more advanced war setting. For example, his experience with bayonet charges could be a shock to the modern - day soldiers he meets in WW2.
One interesting WW2 time travel fanfiction could be about a modern-day historian who travels back to WW2. They might use their knowledge of the war to change small events and see how it affects the overall outcome. For example, they could prevent a key intelligence leak that would have otherwise given the enemy an advantage.
There's also the idea of preventing certain historical events from happening at all. Maybe a time traveler tries to stop the rise of Hitler before he gains too much power. This would involve interfering with the political and social situations in Germany in the early 20th century.
One interesting plot could be a character going back in time to prevent a certain card from being created, which then changes the whole Yu - Gi - Oh! tournament scene. For example, if the Blue - Eyes White Dragon card was never created, how would the power balance shift among duelists?
One interesting plot could be Superman traveling back in time to prevent the destruction of Krypton. He could use his powers to stop the cataclysmic events that led to its downfall. Maybe he tries to convince the Kryptonian council of the impending danger, but faces resistance as they don't believe him at first.
Another plot could be that they travel to a future time where music has evolved into something completely different. They struggle to understand the new forms of music but also bring back some of the old charm from their time, creating a unique blend that revolutionizes the future music scene.
Another plot might be Kratos traveling to a time in the future of his own world. He could see the consequences of his actions and how the world has changed. Maybe he discovers that his actions have led to a new threat emerging, and he has to figure out how to fix it. This would add a new layer of responsibility to his character.
Well, in some time travel Kakashi fanfictions, there's a plot where Kakashi goes back in time right after Obito's 'death'. He tries to save Obito in a different way, not just by taking his eye. He could change the whole course of events that led to the formation of Akatsuki and the many tragedies that followed. This would completely rewrite the story of Naruto in many ways.
One interesting plot could be Octavia traveling back in time to prevent the initial war on Earth. She might use her knowledge of future events to broker peace between the different factions. Another could be her traveling to the time before the Ark was built to see if there were other ways to solve the overpopulation problem without having to send people to the ground in such a dangerous way. And she could also time travel to a future version of the world to see what kind of society has been built after all the chaos on Earth in her original time.
In some pokemon time travel fanfiction, the main character travels to the future. There, they might find that Pokemon have evolved in unexpected ways, like having new types or abilities. They then have to adapt and figure out how to battle with these new forms of Pokemon.