With Kakashi, Kakashi would be extremely worried. He would probably try to find a way to get Naruto out of Akatsuki without causing too much chaos. Naruto, on the other hand, would have to keep his distance from Kakashi to maintain his cover in Akatsuki, which would be a difficult situation for both of them.
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 Kisame might become an interesting one. At first, Kisame would likely be very suspicious of Naruto. But as time goes on, Naruto's determination and strength could earn Kisame's respect. With Itachi there, he might be more open - minded towards Naruto. As for Kakuzu, Naruto would probably constantly clash with him due to Kakuzu's money - loving nature. Naruto would try to convince him that there are more important things than wealth. And with Sasori, Naruto would be horrified by Sasori's use of human puppets and would try to make him see the value of human life.
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.
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 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.
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.
The relationship between Naruto and Sakura would become much more strained yet also more intense. Sakura would be constantly worried about Naruto's safety in Akatsuki. Naruto, on the other hand, would be in a difficult position as he's in an enemy organization but still cares about Sakura and Konoha. His relationships with the Akatsuki members would also be complex. Some might see him as an opportunity, while others might be hostile. Sakura's relationship with the rest of Konoha would also be affected as she tries to support Naruto from afar.
His leadership could bring a sense of unity. Naruto is good at making friends. So, members of the Akatsuki would start to trust each other more under his lead. They would work together better, and their power would be used more effectively.
The storyline would change drastically. Instead of following the path of protecting Konoha, Naruto would be involved in Akatsuki's missions. These missions are often related to capturing tailed beasts, which is the opposite of what he has been doing. So, there would be a complete reversal of his goals.
Well, if Naruto has no emotions in the fanfic, his relationships would become very strange. For example, his bond with Sasuke might not be as intense. Normally, their relationship is full of passion, rivalry, and a deep sense of friendship. But without emotions, Naruto might just see Sasuke as another ninja, not someone he has a strong emotional connection with. His interactions with Sakura would also be different. Instead of having his unrequited love for her, he'd be indifferent, which would change the whole dynamic of their trio.