It will likely make her more responsible. Taking care of a baby is no easy task.
Hinata may become more confident. Dealing with the situation of finding a baby and making decisions about it will force her to be more assertive.
Hinata might become more confident in herself. After seeing Naruto's memories of his own struggles and how he overcame them, she could apply the same principles to her own life. For example, if she sees how Naruto faced his insecurities about being a jinchuriki, she could face her own insecurities about her skills as a ninja more bravely. This would lead to a more well - rounded and strong Hinata.
Perhaps Hinata will be really confused at first. She could ask her friends for help, like Naruto. Together, they would try to figure out where the baby came from and what to do with it. Since Hinata is kind - hearted, she'll surely do her best to keep the baby safe and comfortable.
In such fanfiction, Hinata's actions could potentially stunt Naruto's growth. If she hurts him, Naruto, who is often portrayed as sensitive beneath his bravado, might become more guarded. It could lead to him doubting his own self - worth, especially if the hurt comes from someone he cares about or trusts.
Hinata's family would also have to deal with the emotional aspect. They love Hinata in her normal state, and now they have to adjust to this new form. They might start to remember when Hinata was actually a baby before and all the hopes and dreams they had for her then. Some of the more conservative members of the family might be more hesitant to let Naruto be around her, but the more open - minded ones could see that Naruto's presence is actually good for her in this state. And they would all be united in their goal to get Hinata back to her normal self.
Well, at first, Naruto might be oblivious to Hinata's yandere tendencies. But as they start to surface, it can create a lot of confusion. Hinata's extreme love and possessiveness could make Naruto question her true nature. He might start to pull away from her, which in turn would make Hinata even more desperate to keep him close. It could turn into a cycle of her being overly clingy and Naruto trying to regain his freedom, ultimately affecting the trust and closeness they once had.
In many fanfictions, Hinata's confidence grows. For example, she might start taking on more leadership roles in missions with Naruto. Since she has always been shy, in fanfiction, she could break out of her shell more, especially when Naruto is in danger. She becomes more assertive in protecting him and their relationship.
The author could introduce a backstory for Hinata's bullying. For instance, if she was bullied herself in the past and is now projecting that onto Naruto. As the fanfiction unfolds, she could face her own demons and stop bullying Naruto as she heals from her past traumas.
Hinata may become more assertive. Since she has Naruto as her 'weapon', she has to take on a more leading role. She might have to make decisions about when and how to use Naruto's powers, which could make her grow in confidence.
The parents' relationship could also set an example for Naruto and Hinata. If Kushina and Hinata's mother had a strong, loving relationship, Hinata might be more inspired to be as loving and supportive in her relationship with Naruto. Similarly, Naruto could learn from his father's respect for Hinata's family and carry that forward in his relationship with Hinata.
In these fanfictions, Hinata often develops more confidence. As Naruto's secretary, she has to interact with many people and handle important tasks. For instance, if she has to give presentations on Naruto's behalf, it forces her out of her shell. This new - found confidence can also affect her relationship with Naruto, as she becomes more assertive in expressing her feelings for him.