It might also bring him closer to certain characters. For example, if there are characters in the fanfiction who have experience with sealed chakra or lost powers, they could bond with Naruto over their shared experiences. This could create new and deeper friendships or even romantic relationships as they support each other through the challenges of dealing with Naruto's sealed chakra.
With his chakra sealed, Naruto may face some discrimination from those who previously respected him for his power. This could lead to strained relationships, but also give him the opportunity to prove his worth in other ways, strengthening some relationships in the long run.
It could make his friends more protective. Since Naruto is in a weakened state without his full chakra, his friends might be more concerned about him and try to keep him out of dangerous situations.
It can strengthen Naruto's relationship with his family on a spiritual level. Even though they are sealed within him, he might feel a closer bond to his parents. This could make him more confident in his identity as the son of Minato and Kushina.
Naruto would likely be extremely confused at first. He has always idolized his father, and to have Minato do such a thing would shatter his perception. He'd probably try to talk to Minato, ask him why he's doing it.
His friends might respect his decision more. They know how powerful the Kyuubi's chakra is, but also understand Naruto's reasons for not wanting to use it. This could strengthen their bond as they see Naruto's integrity.
Naruto's chakra mastery affects his relationships in multiple ways. In his friendship with Shikamaru, his chakra control allows him to keep up with Shikamaru's strategic plans during battles. This makes their teamwork seamless. With Hinata, Naruto's powerful chakra makes him more of a hero in her eyes. His chakra also gives him the ability to sense when Hinata is in danger and come to her rescue. Among the villagers, his chakra mastery earns him more respect, which changes the way they interact with him from being skeptical to being admiring.
One reason could be for protection. Maybe in the fanfiction, there are powerful enemies targeting Naruto's chakra specifically. Minato, as his father, seals it away to keep Naruto safe from those who would misuse his power.
Naruto's dense chakra could make his friends either jealous or in awe. If he can do things with his chakra that others can't, some might envy his power. But his true friends like Sasuke and Sakura would be in awe and see it as a way to strengthen their team. For example, Sasuke might see Naruto's dense chakra as a new challenge to keep up with, which could improve their friendly rivalry.
Enemies would definitely be more cautious around Naruto. Those who once underestimated him would now fear his golden chakra. This could lead to some enemies trying to find weaknesses in it. Meanwhile, Naruto's new power might also attract the attention of mysterious characters who want to guide him in using it, which could cause some friction with his existing relationships as he has to decide who to trust.
Perhaps Minato has been corrupted by power. In the fanfiction world, he might have come across some source of power that has twisted his mind. By sealing Naruto's chakra, he could be trying to take that power for himself. It could also be related to some prophecy that he misinterprets. He thinks sealing Naruto's chakra is the key to saving the world, but in reality, it's the opposite.
The sealing of Hashirama can also create new alliances. Clans that were previously at odds might come together to figure out how to deal with the situation. They might share secrets or techniques that were previously hidden in order to find a way to unseal Hashirama or at least mitigate the effects of his absence.
His relationship with Sasuke might change. Sasuke always saw Naruto as a strong rival, and a big part of Naruto's strength was Kurama. Without Kurama, Sasuke might view Naruto differently. Also, Naruto's friends might be more protective of him, as they know he's lost a major source of power.