One possible plot could be that Naruto travels back in time and meets Hashirama during the founding of Konoha. Naruto might be amazed by Hashirama's power and his vision for the village. He could learn from Hashirama about the original ideals of Konoha and bring those lessons back to his own time to make Konoha better.
Their meeting could have a significant impact. Hashirama could gain insights from Naruto about future threats to the ninja world. This might lead him to make different decisions in the founding of Konoha, which could potentially prevent future wars and conflicts.
Naruto's positive attitude and his belief in friendship might make Hashirama more open - minded. For example, if Hashirama was hesitant about an alliance, Naruto could convince him with his own experiences of forming bonds across clans.
There are quite a few out there. 'Time - Twisted Fates' is another one. In this fanfic, Hashirama and Madara are both sent back in time by a strange jutsu gone wrong. It shows their struggle to deal with the knowledge they have of the future while trying not to disrupt the past too much. The descriptions of the ninja world in the past are really vivid.
In many such fanfictions, Naruto and Hinata might be sent back in time through some magical or jutsu - related means. Once they meet their parents, it could be a very emotional moment. Naruto might see his father Minato and mother Kushina, and Hinata could meet her father Hiashi. They could learn a lot about their families' pasts and perhaps even change some things for the better in the timeline.
Well, there's a fanfiction where Naruto travels back and meets Itachi as a young Uchiha. Naruto tries to understand Itachi's motives better and in the process, he gets involved in the internal Uchiha affairs. It's a great read as it shows a different side of Itachi and how Naruto's presence could have changed things. Also, 'Naruto's Time - Jump to the Uchiha Era' is a fanfic that focuses on Naruto learning about the Uchiha's unique abilities and culture during his time - travel adventure.
One idea could be Naruto traveling back in time and meeting Hashirama. He could learn about the founding of the village directly from Hashirama. Maybe Naruto helps Hashirama deal with some early threats to the village that were not well - documented in history.
Another possibility is that Naruto travels to a time when the Uzumaki clan was facing a great threat. He could use his skills and knowledge from the future to help them. Maybe he teams up with young versions of his parents or other Uzumaki members to fight off the enemy. This could lead to a whole new understanding of his heritage and his own powers.
At first, their relationship might be one of confusion. Hashirama has no idea who this strange girl (Fem Naruto) is. But as Fem Naruto shows her strength and knowledge from the future, Hashirama begins to respect her. He might see her as a valuable ally in his goal of creating a unified village.
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.