Well, in the 3rd shinobi war, Naruto would be a game - changer. Given his strong will and his arsenal of jutsu like the Shadow Clone Technique. He could disrupt the enemy's plans. He might also form unexpected alliances with some of the shinobi from that era. And his knowledge of future events (assuming he retains it) could be used to prevent tragedies.
He might change the course of many battles. For example, he could use his Rasengan to take out powerful enemies quickly. His ability to inspire others would also boost the morale of the shinobi on his side.
His powers would be seen as extraordinary. The Rasengan alone would be a very powerful and unheard - of jutsu at that time.
Sasuke could also be the main character. His quest for power and revenge could be further explored in the context of the war. He might find himself in situations where he has to choose between his personal goals and the greater good of his village and the shinobi world.
One idea could be focusing on a young, unknown shinobi who rises to prominence during the war. They might have a unique jutsu that catches everyone's attention.
Well, if Naruto travels to the future in fanfiction, he may encounter his descendants or versions of his friends that have changed a great deal. Maybe he would find that Konoha has evolved into a super - high - tech ninja village. He would need to learn about the new political situations, new enemies, and new ways of being a ninja. For example, he might have to deal with ninjas who can control artificial intelligence as their weapons. He would be confused at first but then use his determination and strong will to figure things out.
In such a fanfiction, Naruto might try to prevent some of the tragedies that occurred in the past. For example, he could stop the Uchiha massacre. He would use his knowledge from the future to change things. Maybe he'd also be able to save some characters who died early in the original story, like Jiraiya. And he could potentially have a huge impact on the relationships between different clans, as he'd know about future conflicts.
In a Naruto time - travel to the Third Shinobi War fanfiction, Naruto could have a huge impact on the power balance. He could team up with younger versions of his mentors and teach them new things. For instance, he could show Kakashi some new ways to use the Sharingan that he learned from watching Kakashi in his own time. He could also influence the development of the Hidden Villages. If he helps a certain village more than he should, it could shift the political dynamics among the villages. And his presence alone could inspire young ninjas to be better and stronger, as they see someone with such unique abilities.
One idea could be to focus on a young, unknown shinobi who rises to prominence during the war. Maybe they discover a new jutsu that changes the tide of a crucial battle.
It could be an original character created specifically for the fanfic. This character could be a young ninja with a unique power or backstory, like a shinobi who has the ability to control plants in combat.
He might be really confused at first. The modern world has so many strange things for him like cars and skyscrapers. He'd probably try to use his ninja skills in unexpected ways, like using his shadow clone jutsu to do multiple tasks at once, like shopping and exploring the city simultaneously.
In a fanfiction scenario, Naruto could bring his ninja skills to the modern Konoha and start a new trend. Maybe he'd teach the modern-day shinobi some of the old - fashioned but effective ninja techniques. Also, he'd be amazed by the new training facilities and the different ways of life. He might struggle with the concept of modern education though, as he was used to the more hands - on ninja training.