Another plot could be Tsuna traveling back to a time when his father was still around. He could get to know his father better and learn some hidden family secrets. This would not only strengthen their relationship but also give Tsuna an edge in his future as the Vongola boss. He might learn about some special powers or techniques that his father knew but never got to pass on to him in the original timeline.
One interesting idea could be Tsuna going back in time to prevent certain tragedies in his family's past. This would change the whole dynamic of the Vongola family in the present.
Hayato Gokudera would be a key character. In the time - travel scenario, he might be initially confused by Tsuna's changed behavior (due to his future knowledge). But then he would quickly side with Tsuna and help him in whatever plans he has. He could also learn from Tsuna's future self and become an even more powerful right - hand man.
One interesting khr time travel story could be about a character going back in time to prevent a great disaster in the khr world. Maybe they go back to a time when a powerful enemy was first emerging and manage to change the course of history so that the khr society doesn't face as much destruction.
Well, a possible plot could be a sort of exchange program between the two worlds. Some Naruto characters are sent to the KHR world for training and vice versa. Naruto himself could learn about the Dying Will Flame in the KHR world and use it in his own way. Meanwhile, Tsuna could pick up some ninja skills in the Naruto world. This would lead to a lot of character development as they adapt to new environments and learn from each other's strengths.
One interesting plot could be Naruto using his ninja skills in the world of Tsuna. For example, he might use his shadow clone jutsu to help Tsuna deal with multiple threats at once. Another could be Naruto teaching Tsuna some of his unique chakra control techniques which could enhance Tsuna's own combat abilities in his world.
Well, a plot could revolve around them building their dream home. Haru might have very specific ideas about how the home should look and feel, while Tsuna is more concerned about the security aspects. They have to compromise and work together to create a home that is perfect for both of them. This could also involve some comical moments when contractors don't understand their requests or there are unexpected problems during construction.
One idea could be Madara traveling back to the era of the Sage of Six Paths. He could try to change the very foundation of ninjutsu, which would create a whole new timeline. Maybe he would attempt to gain the power of the Sage for himself much earlier in history.
One plot idea could be Naruino traveling back in time to prevent a great disaster in their world. Maybe a powerful enemy once defeated them in the past, and by going back, they can change the outcome. Another could be traveling to the future to see how their actions in the present have affected the world. For example, they might find that their current choices led to a utopia or a dystopia.
One plot idea could be Arya traveling back in time to the days before her family's downfall. She could use her knowledge and skills to prevent certain events from happening. For example, she might stop Ned Stark from making some of the political missteps that led to his execution. Another idea is Arya traveling to the future of Westeros. She could see the long - term consequences of the power struggles she was part of and try to change things in her own time. Maybe she'd witness a new dynasty rising or a great war that she could try to avert.
Maybe Chuck travels to the future and discovers that his actions in the present have led to a dystopian world. He then has to go back and make different choices to avoid that future. This could involve complex character development as he grapples with the knowledge of what might be.