One possible reason could be that his newfound 'godlike' powers make his family feel estranged. They might not understand his sudden transformation and the magnitude of his power, which creates a sense of fear or discomfort, leading them to ignore him.
Naruto might initially feel sad and confused. He could try to prove himself to his friends by working hard on his ninja skills. For example, he might train extra hours to show his friends that he is worthy of their attention.
One possible reason could be that the storylines in the fanfiction are focused on different aspects or relationships within the fanfic's universe. Maybe the author wants to explore other characters' interactions more deeply and Naruto just doesn't fit into those particular plotlines they have in mind.
Well, it could mean that Naruto, the character from the Naruto series, is shown as ignoring fan - made fictional works about himself in some kind of fan - created scenario. Maybe in a particular fanfiction story, the plot has Naruto being indifferent to the fan - written tales about his adventures or relationships.
Eventually, Naruto could grow resentful. If the ignoring persists for a long time, he might start to think that Kakashi doesn't care about him at all. This could change Naruto's attitude towards Kakashi and might even make him more rebellious in his training or actions. However, deep down, he still probably hopes for Kakashi's recognition and approval.
Well, it could be about Naruto being overlooked despite his great potential. Maybe he's constantly underestimated by his peers and even some of his teachers. He might secretly develop amazing skills that no one notices until a crucial moment in a battle or some big event.
Naruto could also feel a bit sad and lonely. He's used to being an outcast in the village, but he thought Team 7 would be different. So he might start to question himself. Maybe he'd start training on his own more, trying to become stronger so that they would have to notice him. And he might also try to find other friends outside of Team 7 to fill the void.
The writing quality can also be a factor. If a 'Naruto' fanfic has numerous grammar and spelling mistakes, or if the writing style is very convoluted and hard to follow, it will likely be ignored. Readers want to be able to easily immerse themselves in the 'Naruto' world created by the fanfic, and poor writing can prevent that.
One possible plot could be that Naruto has a godlike power that scares his family. His family, being normal shinobi in comparison, might be intimidated by his power. They don't know how to approach him anymore. Naruto, on the other hand, longs for their acceptance and love like before. He tries to control his power around them, but they still shy away, causing Naruto a great deal of emotional pain.
It might be due to the fanbase loyalty. Fairy Tail fans are really into their own world and characters. They might not want to introduce Naruto elements as they feel it could disrupt the original charm of Fairy Tail. Also, the art styles are different. Naruto has a more traditional Japanese anime look, and Fairy Tail has its own style. This visual difference could be a reason for the lack of crossovers in fanfictions.