One possible plotline could be that Naruto uses his newfound ability to go back in time to prevent some of the tragedies that occurred in the past related to the Bijuu. For example, he might try to stop the initial capture and sealing of the Bijuu into different vessels, which could change the entire history of the ninja world. Another could be that the Bijuu themselves, with Naruto's help, go back to a time when they were free and try to establish a new world order where they are not feared and hunted.
Well, perhaps Naruto and the Bijuu go back in time to the era when the ninja clans were first forming. They could then use their knowledge and power to bring about peace much earlier. The Bijuu might teach the clans about chakra control and the importance of coexistence. Naruto could also use his skills to prevent the formation of some of the more war - hungry clans. This would completely change the history of the shinobi world, and might lead to a more harmonious future in the present day that Naruto originally came from.
A plotline could be that Naruto and the Bijuu go back to a time when the Sage of Six Paths was still alive. They could work with him to better distribute the Bijuu's power in a more balanced way. This might prevent the power struggles that have been going on for centuries. Maybe Naruto would learn new jutsu from the Sage, and the Bijuu would have a chance to exist in a more natural state. It would be a chance for them to rewrite the history of the ninja world from a very early stage.
If Naruto and the Bijuu go back in time, Naruto's relationship with Madara could be completely transformed. Instead of being enemies in the future timeline, Naruto could try to understand Madara's motives from the start and perhaps prevent him from going down the dark path. The Bijuu, on the other hand, might have a different relationship with the Uchiha clan in general. They could offer their power to the Uchiha in a more positive way, rather than being something the Uchiha might try to control in the future.
A possible plotline is that they go back in time and get involved in an ancient Jedi - Sith war. They could use their knowledge from the future to tip the balance in the Jedi's favor. They might also meet their ancestors or past Jedi heroes and learn from them, which in turn helps them in their fight against the dark side in their own time.
They might go back in time and accidentally change something that has a huge ripple effect on the future. So then they have to scramble to fix it before they return to their own time. They could also go back in time to learn some long - lost magic from an ancient wizard or witch and bring that knowledge back to their time to defeat a new dark force.
One possible plotline could be Naruto struggling to come to terms with his half - bijuu nature while also dealing with his relationship with the fem bijuu. Maybe there are other characters who are either afraid or in awe of his unique state, leading to various conflicts.
One possible plotline could be Naruto using his newfound time - traveling ability to prevent some of the major tragedies in the past. For example, he might try to stop the Uchiha massacre. He could also use his knowledge from the future to help his younger self become stronger faster, perhaps by teaching him some advanced jutsu he learned later in life.
One possible plotline could be Naruto using his old and experienced self to prevent past tragedies. For example, he might stop the Uchiha massacre. He could use his knowledge of jutsu and his understanding of people to change the course of history and bring about a more peaceful future from the start.
A plot twist could be that the bijuu themselves have a collective consciousness that Naruto doesn't expect when he absorbs them. This consciousness could start to influence Naruto's actions during his time travels. For instance, they might guide him towards certain events or people that they believe are important for their own reasons. Maybe they want to correct some past wrongs in the ninja world that were related to their existence. This would add an interesting layer to the story as Naruto has to deal with not only the power of the bijuu but also their will.
Ruby could go back in time and end up in a different version of her world. In this new timeline, things are very different from what she knows. She has to adapt quickly and find a way to get back to her own time. Along the way, she meets alternate versions of her friends and foes. She might also discover that the reason she was sent back in time was part of a much larger plan by an unknown force. This could lead to a journey of self - discovery as she tries to understand her role in this grand scheme and how to use it to her advantage.
One possible plotline could be Anduin going back in time to prevent a great war. He might try to change the actions of key figures that led to the conflict in the first place. For example, he could go back and try to reason with Arthas before he fully embraced the Lich King's power. Another plotline could be Anduin going back to learn from the great heroes of the past. He could study under Uther the Lightbringer and gain new insights into the Light, which he could then bring back to his own time to help in the fight against the forces of darkness. And a third plotline could be that Anduin goes back in time accidentally and has to find a way to get back while also not disrupting the timeline too much.
Maybe Team 7 travels back in time to a period when a powerful and evil force first emerged. They then try to stop this force from growing in the first place. Along the way, they face challenges like not being recognized by the people of that time, and having to adapt to the older ways of doing things in the ninja world. They might also encounter versions of their own families or friends in the past and have to deal with the emotional turmoil of seeing them but not being able to fully interact as they are from different times.