One possible plot could be that Naruto accidentally discovers Tsunade in a rather comical situation where she makes an ahegao - like expression. Maybe it's during a failed experiment with a new jutsu. Naruto, being Naruto, is super confused at first but then can't stop laughing. Tsunade gets all flustered and tries to chase Naruto around to keep him quiet. And in the end, they end up having a friendly sparring match as a sort of truce.
The plot could involve a mysterious enemy who uses a genjutsu on Tsunade that makes her make ahegao expressions randomly. Naruto is assigned to protect her until they can break the genjutsu. At first, Naruto is embarrassed by Tsunade's expressions but then realizes it's not her fault. He tries different methods to break the genjutsu, like using his Sage Mode to sense the source of the illusion. Along the way, they have deep conversations about their pasts and how they've both grown, and finally, Naruto manages to break the genjutsu and they celebrate their victory together.
In this fanfiction, the ahegao element could be the catalyst for a new side of their relationship. Let's say Naruto discovers Tsunade in an ahegao state due to some strange chakra fluctuation. He helps her out, and from that moment on, Tsunade starts to view Naruto in a different light. She begins to trust him more with important matters in the village. Naruto, on the other hand, feels more responsible for Tsunade's well - being. This leads to a relationship where they support each other in different ways, whether it's in battles or in dealing with the politics of the village. They become more like comrades who have each other's backs no matter what.
One possible plot could be that Naruto discovers a new jutsu that has hypnotic powers. He accidentally uses it on Tsunade. Under the hypnosis, Tsunade starts to act in uncharacteristic ways. For example, she might start giving out free ramen in the village or change the ninja academy curriculum to something really strange. Naruto then has to figure out how to reverse the hypnosis before it causes too much chaos in the village.
In a fanfiction plot, Naruto might be injured badly during a mission. Tsunade, while treating him, realizes how much he means to her. Naruto, on the other hand, in his semi - conscious state, confesses his love for Tsunade. This event could be the turning point. They start to spend more time together, and Naruto helps Tsunade overcome her fear of losing loved ones again. Eventually, they get married, and Naruto becomes a great support for Tsunade in her Hokage duties, and they build a new era of peace and prosperity in the village.
One possible plot could be that the male Tsunade is a powerful shinobi from another village who comes to Konoha. Naruto befriends him and they end up training together. They learn new jutsus from each other and face challenges within the village, like dealing with rogue ninjas. Along the way, their friendship deepens and they become important allies for each other in the shinobi world.
A plot twist could be that Naruto discovers a secret about Tsunade that she has been hiding all along. It could be something related to her family or a power she has been suppressing. This discovery could either strengthen their relationship or create a rift between them. Also, there could be a twist where an outside force tries to use their relationship to gain power in the ninja world. They might try to manipulate Naruto or Tsunade to their advantage.
One possible plot could be that the female Naruto has to overcome the initial disbelief and discrimination within the village. Tsunade, seeing her potential, takes her under her wing. She trains her not only in physical combat like the Rasengan but also in medical ninjutsu. As she grows stronger, she faces off against new threats to the village, using her unique combination of skills learned from Tsunade and her own natural tenacity. Eventually, she earns the respect of the entire village and becomes a great ninja like her male counterpart was in the original series.
Another aspect could be that it's a story about Tsunade denying Naruto's request for a particular mission or task. Naruto is all eager and raring to go, but Tsunade, as the Hokage, has to think about the bigger picture. So she denies him, and the story could be about how Naruto deals with this denial, how he tries to prove himself worthy to her, and what kind of growth he experiences in the process.
The plot could involve Female Naruto growing up under Tsunade's strict tutelage. Tsunade might train her to be a fearless and powerful kunoichi. She could be sent on special missions that require both combat skills and medical knowledge. Maybe she has to deal with a new threat to the Leaf Village, and uses her connection to Tsunade and her own wits to find a solution.
If Naruto was adopted by Tsunade in fanfiction, he would probably be exposed to a different set of values. Tsunade is a strong - willed and sometimes reckless woman. Naruto could pick up on her fearless attitude towards battle and also her more practical approach to leadership. Also, their relationship might change the power dynamics in the village a bit, as Naruto would be directly under Tsunade's wing.
One possible plot could be that Tsunade kidnaps Naruto because she believes an enemy is after him and she wants to keep him safe in a secret location. She might think that by taking him away from the village, she can train him without any distractions or threats.