Well, he might time travel to a point in history where a powerful and dangerous jutsu was created. Being pregnant, Naruto has to be extra cautious, but his determination to protect his future child drives him to try and stop the jutsu from being misused. He could also interact with past versions of his friends and allies, and they would be shocked to see him pregnant. This would lead to some interesting character dynamics as they try to understand how this happened and help Naruto achieve his goals.
Perhaps Naruto time travels to a future where his child is grown up. While pregnant, he gets a glimpse of what his child's life could be like and the kind of world they will grow up in. This could inspire him to make changes in the present (his original time) to ensure a better future for his unborn baby. Or, he could travel to a time during a great war and his pregnancy becomes a symbol of hope for the war - torn shinobi, motivating them to fight for a better future for the next generation.
One plot idea could be that Naruto, while pregnant, travels back in time to the founding of Konoha. He uses his knowledge of the future to prevent certain tragedies from occurring during the village's creation, all while dealing with the physical and emotional challenges of being pregnant in a different time. Another could be that he travels to a time when the Uchiha clan was still intact and tries to change the events that led to their downfall, with his pregnancy adding an extra layer of complexity as he has to protect his unborn child too.
One idea could be that Naruto travels back in time while pregnant and tries to prevent certain tragedies in the village. For example, he could stop the Uchiha massacre. Since he is pregnant, he might have an even stronger motivation to create a peaceful world for his unborn child.
One idea could be exploring how Naruto's friends react to his pregnancy. They might be shocked at first but then become very protective. Another could be how Naruto copes with the physical and emotional changes during pregnancy while still being a ninja.
One idea could be Naruto going back to the time of the First Hokage to prevent a dark jutsu from being created that later causes chaos in his own time. He could use his knowledge of future events and his powerful jutsu to stop the wrongdoings.
One idea could be exploring the wife's time travels to different historical events not shown in the original. For example, she could travel to the signing of the Declaration of Independence. Another could be a story where the husband also gains the ability to time travel briefly and they have to figure out how to manage their travels together. And perhaps a plot where the wife travels to a future time and sees how their relationship impacts future generations.
Perhaps there is a prophecy that a union between them would result in a special child. They initially resist the idea but as the pregnancy progresses, they start to embrace the new situation and work together to protect the unborn child from those who might want to harm it. They also have to face the challenges of changing their relationship from rivals to co - parents.
One possible plot idea could be about how Naruto has to deal with the various emotions and needs of the pregnant members of his harem. He might have to balance his ninja duties with taking care of them.
One idea could be that a female character in the Naruto universe discovers she's pregnant during a time of great turmoil. Maybe she's a ninja who has to balance her pregnancy with her duties. For example, Sakura could find out she's pregnant while also being in the middle of a major medical emergency in the village. Another plot could involve a new character, perhaps an outsider, who comes to the village pregnant and has to adapt to the Naruto world while carrying a child. A third plot might be about a male character having to deal with his partner's pregnancy, like Naruto supporting Hinata during her pregnancy and all the challenges that come with it, like protecting her from potential threats.
Perhaps there could be a plot where an enemy tries to target Hinata because of her pregnancy, seeing it as a way to get to Naruto. Naruto then has to go to great lengths to protect her and their unborn child. This could lead to some intense battles and also show the deep love Naruto has for Hinata and their future family.
One interesting plot idea could be Naruto using his future knowledge to prevent certain tragedies. For example, he might be able to save some of the ninjas who died in the original war. Another idea is that he could change the power dynamics between the villages. Maybe he teams up with a younger version of an enemy ninja and they form an unexpected alliance that changes the course of the war.
Well, a possible plot could be centered around their journey to prepare for the baby. They might travel to different places to find the best midwife or special herbs for a healthy pregnancy. Also, there could be a sub - plot where their friends, like Sasuke and Sakura, help them train while Naruko is pregnant so that she can still defend herself if needed. It could add an interesting dynamic to the story.