Well, Naruto might become more confident in his new form. Since he's a man now, he could have a different way of approaching battles. He might be less impulsive and more strategic, which would be an interesting development from his usually head - on style.
His relationships with other characters would surely develop. For example, his bond with Kakashi could change as they now might have more of an equal footing. And with his female friends, there could be a shift from a more friendly - brotherly relationship to something more complex, as he's now a man. He might also gain more respect from some of the older ninja in the village who previously saw him as just a rambunctious kid.
Naruto's self - perception would change dramatically. He has always been seen as the underdog, the kid with a big heart but not always taken seriously. As a man, he'd demand respect and recognition. This could lead to him becoming more of a leader figure. He might also start to understand the sacrifices his father made in a different way, as he now has a more adult perspective on life and the responsibilities that come with power and age.
Another aspect could be that Naruto's baby form has some unique abilities or auras. Maybe his presence as a baby has a calming effect on some of the more aggressive characters in the Naruto world. His friends could also discover new things about his past or his family through his baby state, like finding a hidden mark on his body that gives clues about his heritage.
Well, one interesting plot could be Naruto, as a female, having to deal with different social expectations in the ninja world. For example, she might face more challenges in being taken seriously as a strong fighter since there are some gender biases in the original Naruto world. Another could be her new relationships with other characters. Maybe she forms a different kind of bond with Sasuke, not just as a rival but in a more complex, perhaps more emotionally charged way.
Naruto would definitely have a huge character development. At first, he might be confused and a bit frustrated about the change. But as time goes on, he could learn to embrace his new form. He might become more empathetic towards the female characters in the village, understanding the challenges they face. Sakura, on the other hand, would feel guilty for the accidental transformation. She would strive to find a way to turn Naruto back, which could lead to her developing her medical ninjutsu skills further.
In this type of fanfiction, often Naruto's transformation into the nine - tailed fox can lead to some really cool battle scenes. He could use the fox's speed and strength in unique ways. Like, he might be able to run up walls or jump extremely high to attack enemies from unexpected angles. Also, there could be a plot where Naruto has to enter a sort of spiritual realm within himself to communicate with the nine - tailed fox and gain better control over their combined form.
Naruto might develop a deeper understanding of the power of friendship and how it can cross enemy lines. His act of saving Haku could make him more determined to see the good in everyone. For Haku, he could start to question his loyalty to Zabuza and consider a different way of life, which is a significant character development.
His relationships with his friends could evolve in interesting ways. His friends might be in awe of his wings at first, but then they would need to adapt to the new Naruto. Sasuke, for instance, could be initially jealous of Naruto's new ability but later come to respect it. Naruto himself would have to learn to trust his friends with his new secret and rely on them for support when dealing with any negative reactions from the village.
One interesting plot development could be Clary struggling to control her new vampire instincts while still trying to protect her friends. She might have a hard time dealing with the thirst for blood and not wanting to harm the people she loves.
Naruto could develop a more refined and sophisticated side. The suit symbolizes a new level of maturity. He might become more aware of the political and diplomatic aspects of being a ninja leader. For example, he starts to use more words and less brute force in negotiations.
Albedo might become more empathetic. As a girl, he could experience different social interactions and emotions. He might also become more aware of his appearance and how others perceive him. For example, he could start to care more about his clothing and grooming.
Well, at first, Jack Frost as a human might be very confused. He could be disoriented by all the new sensations and the lack of his ice powers. But as time goes on, he might start to appreciate the simple pleasures of being human, like the warmth of a hug or the taste of hot chocolate.