Another interesting development could be both of them learning from each other's strengths. Sasuke could learn the value of having strong bonds from Naruto, while Naruto could gain a better understanding of the power of self - reliance from Sasuke. This mutual learning could change their characters and their relationship in the fanfiction.
In this fanfiction, Naruto could develop a new set of skills related to childcare. He would learn how to make baby Sasuke happy, feed him, and put him to sleep. Sasuke, on the other hand, could start to see Naruto as a true brother figure from a very young age, which would shape his personality and relationships in the future.
For Naruto, he would have to grapple with the fact that he is fighting his former friend. This could make him more solemn and determined. He might develop a darker side as he realizes the seriousness of stopping Sasuke. For Sasuke, he could start as overconfident in his power but as Naruto keeps pushing him back, he could become more desperate and start to question his own motives.
For Naruto, as a female, she might become more confident in her femininity while still maintaining her strong ninja spirit. She would grow in her ability to understand Sasuke on a deeper level. Sasuke, on the other hand, would become more empathetic. His cold exterior would soften as he is influenced by Naruto's warmth. He would also learn to be more domestic, sharing responsibilities in their relationship.
For Naruto, running away might make him more determined to prove his worth and protect his friends. He could learn to control his Nine - Tails chakra better in the face of danger outside the village. Sasuke may start to trust Naruto and Sakura more, realizing that they are his true comrades. Sakura, on the other hand, could become more independent and confident in her abilities, not just relying on Sasuke and Naruto but also being able to take charge when needed.
For Naruto, he might become more determined to bring Sasuke back to the right path. The fight in the bathroom could be a turning point where he realizes that he can't just use words but also has to show his strength. Sasuke, on the other hand, could start to question his own motives a bit more. Maybe seeing Naruto's unwavering spirit in such a strange setting makes him think twice about his actions.
In many Naruto fanfictions that depict Naruto and Sasuke as bonded brothers, their relationship often goes through various challenges. They might support each other more directly. For example, Sasuke could be more open about his feelings and not be so easily swayed by revenge. Naruto, on the other hand, would have an even stronger ally in Sasuke, and they could face the Akatsuki together more effectively. Their bond could also lead to new jutsu development as they train together and understand each other's strengths and weaknesses better.
For Naruto, being turned into a girl could lead to a development where he becomes more aware of his appearance and how he presents himself. This could be a new experience for him, and he might use it to his advantage in some social situations within the ninja world. Sasuke, now as a girl, may find that she has a newfound sense of community. She could start to rely on others more and build stronger bonds with the people around her, which is a big change from her usually solitary nature.
Sasuke's character would likely become more complex. His act of killing Danzo could push him further into the realm of darkness or, paradoxically, start his journey towards redemption as he realizes the full weight of his actions. Danzo's character, in death, could be revealed in different lights. Maybe his true motives for his actions throughout his life are uncovered, which could affect how other characters view Sasuke's killing of him.
For Hinata, her development from a shy girl to a confident ninja is always great to read about in fanfiction. Sakura's growth from being just a girl with a crush on Sasuke to a powerful medical ninja is also a good one. Ino's development in terms of her psychic abilities and her relationship with the other characters can be interesting. Naruto's growth as a leader is often explored well in these fanfictions too.
The Sakura, Sasuke, Naruto love triangle in fanfiction is really interesting. Naruto is the underdog in terms of Sakura's love initially. He is always there for her, while Sasuke is more aloof. In some fanfictions, there are alternate universes where Sakura realizes Naruto's worth earlier. Some fanfictions focus on how Sasuke's actions affect both Sakura and Naruto's relationship, and how they all navigate their complex feelings for each other.