His relationship with Sasuke would become even more complex. Sasuke might be suspicious of Naruto's motives for joining Akatsuki, thinking he has truly turned to the 'dark side'. Or, they could end up on opposite sides of a conflict within Akatsuki itself if their goals within the organization differ.
With his friends in Konoha, they would be devastated and confused. His closest friends like Sakura and Kakashi would probably try to bring him back. They would see his joining Akatsuki as a betrayal at first, but later might realize there are deeper reasons behind it. Naruto would also have to deal with new relationships within Akatsuki. Some members might see him as a valuable asset, while others might be wary of his loyalty and his different ideals compared to the rest of the group.
Naruto's relationship with the Jinchuriki that Akatsuki has been hunting would be very different. Instead of being their protector, he would be in the same organization as their captors. He might try to protect them from within Akatsuki, which would put him at odds with some of the more ruthless members. Also, his relationship with the Akatsuki leader, whether it's Pain or someone else, would be a power struggle of sorts. Naruto would want to influence the organization's actions towards a more positive direction, while the leader would want to keep Naruto in line with their original goals.
Naruto joining Akatsuki in fanfiction would turn his relationships upside down. His friends in the Leaf would initially feel betrayed. However, some might start to question if there's more to Naruto's decision. His relationship with Akatsuki members would be a mix. He'd be constantly in a tug - of - war with Itachi, who has his own plans regarding Naruto. And his interactions with Pain would be intense, as Pain represents a very different ideology from Naruto's. Naruto would have to struggle to find common ground or at least a way to coexist with these new 'comrades' while still holding onto his own values.
If Naruto joined the Akatsuki, his relationship with the other Akatsuki members would be diverse. Some, like Hidan, might see him as an enemy no matter what. But others, like Konan, might be more open to him. She has a more complex view of things compared to some of the more blood - thirsty members. Naruto would also have to deal with the Akatsuki's leader, Pein. Their relationship could range from mutual respect to outright hostility depending on Naruto's actions and goals within the organization.
His relationships would be completely turned upside down. His friends in the Leaf Village would be confused and hurt. Meanwhile, in Akatsuki, he'd have to build new relationships. Some members might be hostile at first, but others could potentially become comrades. For example, he might form an unlikely bond with Hidan, who is very different from Naruto in beliefs but they could learn from each other in a strange way.
His personality might become more guarded. He'd be surrounded by people who are mostly out for themselves or have very different values from him. So, he'd need to be more cautious in showing his true self.
If Naruto was trained by the Akatsuki in fanfiction, his relationships would be completely transformed. For starters, his relationship with Kakashi would be strained. Kakashi has always been Naruto's mentor in a way, and seeing Naruto side with the Akatsuki would be a shock. His friends like Sakura and Shikamaru would also be confused and probably try to bring him back to the 'right side'. And his relationship with the villagers of Konoha would turn sour as they would fear his new - found Akatsuki - related powers.
Regarding Kisame, Naruto's positive and energetic attitude could be a shock to him. Kisame might start to question his own loyalty to the Akatsuki as Naruto tries to bring a different perspective. Their relationship could be one of constant friction and yet also a bit of mutual respect as Naruto doesn't shy away from Kisame's power.
His relationship with his friends in Konoha would be severely strained. They would likely feel hurt and confused by his sudden departure. On the other hand, in Kiri, he would have to build new relationships from scratch. He might initially be an outcast but gradually earn the respect of some Kiri ninjas.
His relationship with Sasuke would become even more complex. Sasuke might see Naruto's joining of Akatsuki as a betrayal or a sign that Naruto has finally given up on Konoha. Naruto's old friends in Konoha, like Sakura and Kakashi, would be very confused and hurt. They might try to bring him back, but also be wary of his new Akatsuki ties. And within Akatsuki, Naruto would have to navigate relationships with members who have different motives and personalities, some of whom might not trust him at all.
His relationships with his old friends in the Hidden Leaf would become extremely strained. They would see him as a traitor. For example, Sakura might be heartbroken and angry at him. Kakashi would be disappointed. However, within Akatsuki, he could form new relationships. He might become friends with some of the members who have a similar background of being misunderstood. For instance, he could bond with Hidan over their strong beliefs, though their beliefs are very different in nature.
Naruto's relationship with his sensei, Kakashi, would be severely strained. Kakashi has always been a guiding figure for Naruto, and Naruto joining the Akatsuki would seem like a betrayal. However, Kakashi might also suspect that Naruto has an ulterior motive. As for his relationships with the other Konoha ninjas, they would be filled with suspicion and mistrust. But Naruto could also form new relationships within the Akatsuki. He might befriend some of the members who have a bit of good in them, like Konan perhaps, and together they could work towards a new future for the Akatsuki.