Maybe in the fanfiction, Naruto's seventh time travel takes him to a point where he meets his parents as children. He then has to make sure not to disrupt the timeline while also trying to understand their lives better. This could lead to some really heart - warming and also tense moments as he struggles to keep his identity a secret and yet interact with them.
In this fanfiction, it could be that Naruto's time travel causes a split in the timeline. He ends up in a world where the Akatsuki has actually achieved their goal of world domination. He has to figure out how to use his knowledge from his original timeline to not only survive but also try to reverse the situation. This would involve making alliances with some unexpected characters and using his jutsu in new and creative ways.
One interesting plot twist could be that Naruto travels back in time and discovers that the Hidden Leaf Village was founded on a much darker secret than he ever knew. This changes his perception of the village's history and his role in it.
Well, a cool plot twist could be that Naruto and Mito time travel to a period right before the Nine - Tails was sealed in Mito. Naruto, with his knowledge of the future, tries to find an alternative way to deal with the Nine - Tails' power. This could completely change the history of the Uzumaki clan and the Hidden Leaf. Also, they could time travel to a time when the first Hokage was still alive and Naruto has to convince him of future threats without revealing too much. Or perhaps they travel to a time when a powerful enemy was about to attack the village, and they use their future skills to defeat the enemy in a way that shocks everyone in the past.
Maybe they travel back to their early days at the ninja academy. Naruto, who now has all his future knowledge, tries to befriend Sasuke in a different way. But Sasuke, being suspicious, thinks Naruto has some ulterior motive. This leads to a whole new set of comical and at the same time tense interactions between them as they both have to deal with their past selves and the changes they want to make.
Perhaps a really cool plot twist is that the time travel was actually a trap set by an old enemy. When Kakashi and Naruto travel back, they find out that this enemy has been manipulating events from the past all along. They then have to not only fix the past but also figure out a way to stop this enemy from using the past to destroy their future.
One interesting plot twist could be that the Sannin travel back to a time when Orochimaru was still a good - hearted ninja. They could try to prevent his fall to the dark side. This would change the entire future of the Naruto world as Orochimaru's actions had a huge impact on many events.
One interesting plot twist could be that female Naruto, with her knowledge of the future, tries to prevent Madara from making certain mistakes that led to his downfall in the original timeline. For example, she might show him the true nature of the power he was seeking, making him question his motives.
A plot twist could be that Sakumo, when traveling back in time with Fem Naruto, realizes that he can use the knowledge of the future to his advantage in ways he didn't expect. He might find out that some of the people he thought were enemies in his original time were actually being manipulated. This new knowledge could lead to him forming unexpected alliances and changing the course of history for the better. Also, Fem Naruto's different approach to problems compared to the male Naruto could influence Sakumo's decisions in a way that completely alters the future.
One interesting plot twist could be Naruto changing the past in a way that completely alters the future relationships. For example, if he manages to prevent certain tragedies from happening to his friends' families, it could lead to very different dynamics. Maybe Sasuke's family wouldn't be massacred, and Sasuke would grow up in a completely different environment, which might change his entire attitude towards the village and Naruto himself. This could lead to a whole new set of adventures and challenges for Naruto as he tries to adapt to this new timeline.
One interesting plot twist could be that when they travel back in time, they accidentally change an event that was crucial for the formation of their friendship. So instead of being friends or at least allies later in life, they become enemies in the new timeline. Another could be that they go back to a time when their villages were at war, and they have to work together secretly to stop the war without revealing their time - traveling identities.
One interesting plot twist is if they time travel and find that the world they end up in has a different version of the Chakra system. They have to adapt quickly to this new form of energy while also trying to find a way back home. Also, imagine if they time travel and discover that Naruto was supposed to be born in a different village in this alternate timeline. This would completely change the way they view Naruto's destiny and their role in protecting him.
One interesting plot twist could be that in the past, Fem Naruto's presence disrupts the established power balance. For example, her unique jutsu, which might be a blend of her original male counterpart's skills and some feminine twists, catches the attention of all the clans. Hashirama, instead of immediately trusting her, is initially suspicious, thinking she might be an enemy spy sent from a future where the villages are at war again. This forces Fem Naruto to prove herself in ways she never expected, like having to participate in a clan - based tournament to show her worth and loyalty to the budding village.