Yes, there could be. Some fanfiction writers are creative enough to come up with a story where Naruto and Erza interact in a way that is suitable for all ages. For example, they might be in a shared adventure in a new world where some strange magic or power causes a false pregnancy - like situation as part of the plot mystery, rather than anything inappropriate.
There could be such a fanfiction. Fanfiction writers often come up with all kinds of creative and sometimes out - of - the - box ideas. However, I haven't personally come across one where Natsu gets Erza pregnant. It might be a rather niche concept within the Fairy Tail fanfiction community, as most fanfictions tend to focus on different aspects of the characters' relationships, like friendship, adventure - related partnerships, or other forms of romantic development.
In a non - adult take on this fanfiction, it could start with Naruto and Erza being accidentally transported to a parallel dimension. In this dimension, there is a unique energy that affects Erza's body in a way that seems like she is pregnant. They have to figure out how to get back to their own worlds while also dealing with this new situation. Along the journey, they meet various characters from both Naruto and Fairy Tail universes who are also trapped in this dimension, and together they work towards a solution.
One possible plot could be that Erza discovers she's pregnant and has to deal with the shock while still being part of her guild and its adventures. She might worry about how it will affect her ability to fight and protect her friends.
It could be one of her close friends from the guild. Maybe Jellal, considering their complex relationship in the original story. There's already a lot of history between them, and this could be a new development in their relationship.
There might be such fanfictions in the vast world of Fairy Tail fanfiction, but I haven't specifically come across one. Fanfiction often explores various relationships and scenarios that are not part of the original canon, so it's possible for creative fans to write such a plot.
In Erza's world, there could be a dark mage who wants to use the power of the unborn child for their own evil purposes. They might see the combination of Naruto's ninja abilities and Erza's magic in the child as a great source of power and will stop at nothing to get their hands on it.
I'm not sure if there is an exact 'Naruto Pregnant Erza' fanfic. Fanfic topics can be very diverse, and this is a rather unusual crossover concept. You might try searching on some major fanfic websites like FanFiction.net or Archive of Our Own, but there's no guarantee you'll find one.
Yes, there are likely some 'Naruto Gets Pregnant' fanfictions out there in the vast world of fan - created content. However, such concepts often deviate from the original source material in very extreme ways.
One possible plot could be that Naruto and Erza are from different universes that somehow collide. They meet and fall in love against all odds. When they find out Erza is pregnant, they have to face challenges from both of their worlds. Naruto's ninja village might be skeptical about his relationship with someone from another realm, and Erza's guildmates in Fairy Tail could also have concerns. But together, they strive to protect their unborn child and find a way to make their two worlds coexist peacefully.