In this fanfic, Acnologia might join Fairy Tail under mysterious circumstances. Maybe he has lost his memory and the guild takes him in. As he stays with Fairy Tail, he begins to regain his memories bit by bit. His relationship with the members would be complex. Some might fear him, while others like Natsu might see him as a rival to overcome. But in the end, he could use his power to protect the guild from a threat that only he could face, forging a new identity within Fairy Tail as a protector rather than a destroyer.
One possible plot could be that Acnologia, with his immense power, initially causes chaos within Fairy Tail. The members are both in awe and afraid of him. But as time passes, he starts to understand the concept of friendship and loyalty in Fairy Tail. He could then use his power to protect the guild from other major threats, like the Alvarez Empire. This would completely change the power dynamics in the Fairy Tail world.
There could be a lot of character development. Maybe she has a troubled past that she shares with the members of Fairy Tail, which helps her grow closer to them and become a more empathetic character. She might also learn the value of friendship within the guild, which could change her whole perspective.
One possible plot could be that Igneel's arrival in Fairy Tail brings a new level of power and protection. He could start training the mages in new and powerful dragon - slaying magic, making Fairy Tail even more formidable against their enemies.
The plot could involve Kagome bringing her spiritual powers and archery skills to Fairy Tail. Maybe she'd form a team with some of the guild's mages and go on adventures. She could use her holy powers to combat dark magic threats in the Fairy Tail world.
The plot might revolve around Yukino's journey of self - discovery within Fairy Tail. At first, she might feel like an outsider, but as she gets involved in the guild's daily activities, she starts to find her true self. For example, she could participate in the Grand Magic Games as a representative of Fairy Tail. During the games, she showcases her skills and also learns about the value of teamwork and friendship within the guild.
Well, one possibility is that Natsu could join Fairy Tail in a different way than in the original story. Maybe he has some special mission before officially becoming a member. For example, he has to prove his loyalty by helping an elder member with a personal problem.
Some members might be initially cautious. Given her past as a powerful and somewhat feared being, they would be worried about her true intentions. For example, Gray might be on guard until he sees her actions are genuine.
One possible plot could be that Natsu has been living a different life away from Fairy Tail. Maybe he was raised by another guild unknowingly. When he finally joins Fairy Tail later, he has to prove himself to the existing members who are skeptical of his late arrival. He might have unique magic skills he developed elsewhere that surprise everyone.
One possible plot could be Sasuke initially being a bit of an outcast in Fairy Tail because of his brooding nature. But as he goes on quests with the guild members, he starts to open up. For example, he might team up with Natsu for a mission where they have to fight a powerful dark wizard. Through their battles and interactions, Sasuke learns about the power of friendship in Fairy Tail, which is very different from his past experiences in Naruto's world.
One possible plot could be that Natsu and Mirajane join Fairy Tail at different times. Natsu might bring his usual enthusiasm and powerful fire - based magic. He could quickly get into all sorts of adventures, making friends and enemies alike. Mirajane, on the other hand, could use her Take - Over magic to be a great asset in battles. Their joining could lead to new team - ups within the guild, like Natsu and Mirajane going on a mission together to stop a dark wizard who is causing chaos in a nearby town. They'd face challenges, but their combined skills would help them overcome the odds.