Well, it depends on how it's written. If it's written in a respectful and tasteful way that adheres to ethical and moral standards, it could be okay. However, if it involves inappropriate or vulgar content, then it's not acceptable.
Maybe by adding some unique plot elements. Like, the pregnancy could be a result of some special power or situation. And then the story could revolve around how she manages the mission with this new condition, her relationship with her teammates, and how they support her.
Well, apart from Naruto and Hinata, their friends could also be important characters. For example, Sakura could be Hinata's doctor during the pregnancy, providing medical advice. And Kakashi could offer some wisdom to Naruto about being a father, so they are also sort of secondary main characters in the fanfic.
One possible plot could be that Naruto and Hinata find out about the pregnancy and they are both overjoyed. They start preparing for the baby's arrival, with Naruto being super protective of Hinata. He might go on missions less often to be around her. Hinata, on the other hand, could be seen knitting baby clothes and daydreaming about their future family life.
Well, perhaps in the fanfic, Naruto is away on a mission when Hinata discovers she's pregnant. She then has to deal with the initial shock and excitement all by herself. But she's strong, and she starts taking care of herself and the unborn baby. When Naruto returns, he's overjoyed and vows to protect his family even more fiercely. And they could have a little ceremony in the village to celebrate the upcoming addition to their family.
The antagonists could be some members of their own clan who oppose the union or the pregnancy for various reasons, such as concerns about bloodline purity or political power within the clan. They might try to undermine Neji and Hinata's relationship and the pregnancy.
Naruto would be over the moon. He's always been a family - oriented person deep down. He'd probably start blabbing to all his friends about how amazing Hinata is and how excited he is to be a father.
Perhaps the story could start with Hinata revealing her pregnancy to Neji. Neji is initially shocked but then quickly embraces the idea of being an important figure in the child's life. As the pregnancy progresses, they face challenges like Hinata's health issues due to her delicate state. Neji uses his skills and knowledge to find remedies and support her. They also plan for the future of the baby, thinking about what kind of ninja the child will become.
On the spy mission, their relationship is bound to evolve. The secrecy and danger of the mission create an environment where they have no one else to turn to but each other. Hinata, with her shy nature, might start to become more confident around Naruto as they work side by side. Naruto, on the other hand, will notice Hinata's intelligence and courage more. They might have quiet moments during the mission, perhaps hiding from enemies in a small space, where they share their hopes and dreams for the future. These shared moments will strengthen their bond, and they may even start to fall in love more deeply as they see each other in new and different lights during the spy mission.
One possible scenario in this fanfiction could be how Shikamaru, with his laid - back yet intelligent nature, would handle Hinata's pregnancy. He might use his strategic mind to plan for the baby's future, from financial aspects to educational opportunities. Maybe he'd be a bit flustered at first, but then quickly adapt and become a very supportive partner.