What could be the reasons for Naruto and Sasuke to leave Konoha in fanfiction?

One reason could be to seek a new life away from the constraints of Konoha. Maybe they feel that they can't fully grow or explore their potential within the village. Another reason might be to protect Konoha in their own way. They could believe that leaving and dealing with threats from the outside would keep the village safer.

One reason could be a special mission. For example, there might be a threat that only Naruto can help with in Suna. Maybe there's a new type of enemy that has some connection to Suna's unique chakra sources and Naruto's abilities are needed to figure it out.

One possible reason could be to seek new powers. Maybe they feel that Konoha no longer offers the kind of training or opportunities they need to grow stronger. Another reason might be to escape from certain politics or social pressures within the village. For example, Naruto has always been an outcast in some ways, and Ino might be tired of the family business or the way things are done in Konoha.

Another reason might be that Naruto is seeking a greater purpose. In the fanfiction, his 'godlike' state could make him realize that there are threats out there that he can't face while being tied to Konoha. He may leave to protect the world on a larger scale, believing that he can be more effective away from the village.

Perhaps in a fanfiction, Sasuke discovers a new and extremely dangerous power that he can't control and it starts to endanger Konoha. Naruto tries to stop him but in the heat of the battle, accidentally kills him. Overwhelmed with guilt and feeling that the village will never understand, Naruto leaves. But this is a very different take on their relationship and the Naruto world as a whole.

One reason could be that he feels betrayed in Konoha. Maybe some secrets were uncovered about the village's past actions towards him or his family that made him lose faith. So, he decides to start anew in Kiri where he hopes to find a different kind of acceptance.

Another possibility is that they leave because of a sense of disillusionment. They could have witnessed some corruption or unfairness within Konoha's leadership or among the ninja community. This makes them lose faith in the village and decide to start anew elsewhere.

One possible reason could be to search for a powerful artifact. In many fanfictions, there are often hidden and powerful items that can change the fate of a village or even the whole ninja world. Naruto and Tsunade might leave Konoha to find such an item before their enemies do. This would be a dangerous mission, so they keep it a secret from the rest of the village to avoid panic.

One reason could be to seek greater power. In fanfiction, the world outside Konoha might be seen as having more opportunities for growth. They might want to train with different masters or learn unique jutsu not available in Konoha.

In fanfiction, it could be due to a new threat that Konoha refuses to take seriously. Suppose there's a new and extremely dangerous enemy on the rise, and Konoha's leadership decides to ignore it or handle it in a way Naruto and Sasuke don't agree with. They might then choose to leave Konoha to face this threat on their own terms, believing that they can't do it while being restricted by Konoha's rules.