A possible plot in izuku goes back in time fanfiction is that Izuku goes back to a crucial moment in hero history. Let's say he goes back to the time of the first major villain attack that the heroes struggled to deal with. With his knowledge of future strategies and hero abilities, he could help the heroes win more easily. This would not only change the perception of heroes at that time but also change the way hero training and strategies are developed in the future. And he could also use this opportunity to form closer relationships with the heroes of that era, which would be very different from his original experience.
One interesting plot could be Izuku going back in time and using his future knowledge to prevent certain tragedies. For example, he might stop the initial injury that All Might received, which could change the whole course of the story. Another plot could be him going back to his own childhood and being able to train better and earlier, thus becoming an even stronger hero. He could also use his knowledge of future villains to stop them before they become a major threat.
One interesting plot could be Snape going back and trying to prevent the death of Lily. He might use his knowledge of the future to change certain events that led to her demise. Maybe he would try to expose Pettigrew earlier or find a way to make James Potter more cautious.
Maybe in the fanfiction, Aang goes back in time and meets his past self. He then has to guide his younger self without disrupting the timeline too much. This could lead to some really cool moments of self - discovery for Aang, as he sees himself from an outside perspective and realizes how much he has grown.
Well, in 'Bilbo goes back in time' fanfiction, a possible plot is that Bilbo goes back to the time before Smaug took over the Lonely Mountain. He could then try to warn the dwarves and help them better prepare for the dragon's arrival. This might involve him teaching them new battle strategies or helping them find a better hiding place for their treasures. Another interesting idea is that Bilbo travels back to the time of the great elven kingdoms' prime. He could experience the height of elven culture and maybe even learn some ancient elven magic that he could bring back to his own time.
One interesting plot could be Stiles going back in time and trying to prevent a major tragedy from happening in the past that has consequences in his present. For example, he might stop a villain from getting a powerful artifact that later causes chaos in his own time.
One interesting plot could be Hermione going back in time and preventing certain tragedies from the original story. For example, she might stop the death of a beloved character. Another could be her using her modern - day knowledge to change the course of wizarding history, like introducing new spells or concepts earlier.
In some fanfictions, Harry goes back in time and decides to train himself better. He could seek out different magical knowledge or combat skills that he didn't have the first time around, which then changes his future interactions and battles. For example, he might learn ancient spells that give him an edge against Voldemort.
One interesting plot could be that Bella goes back in time and tries to prevent certain events from the original story that led to pain or danger. For example, she might stop James from hunting her in the first place.
Well, a cool plot in an Arya Stark goes back in time fanfiction could be that she travels back to the time when the White Walkers first started to become a threat. Arya, with her knowledge of the future, could try to find a way to stop them from ever becoming such a powerful force. Maybe she'd team up with some of the early Night's Watch members in a way that changes the entire history of the war against the dead. Also, she could go back to the time when the Starks were still in a more powerful position in the Seven Kingdoms and use her skills to strengthen their alliances.
One interesting plot could be Kurama using his knowledge from the future to prevent certain tragedies in Naruto's past. For example, he might stop Orochimaru's early attacks on Konoha more effectively. Another plot could be Kurama helping Naruto train earlier and more efficiently, leading to Naruto becoming much stronger at a younger age. And perhaps Kurama could also change some of the relationships within the village, like improving Naruto's standing among the villagers much sooner.
One possible plot could be that godlike Izuku uses his newfound powers to go back and prevent certain tragedies in the past. For example, he might stop the initial attack that led to so much chaos in his world. He could also use his knowledge of the future to help his friends earlier, like giving Midoriya tips on how to control his quirk better from the start.