It would definitely shock their friends. Naruto, for instance, would be caught in a difficult position as he is a close friend to both. He would probably try to mediate but might not be successful.
On a broader scale, it could change the power dynamics in the village. Sakura is a strong kunoichi in her own right. If she is divorced, she might become more independent and focus more on her own career and abilities, which could lead to new alliances or rivalries within the village. And Sasuke, who is already a bit of an outsider, might become even more withdrawn, affecting how the village views and interacts with him.
The Uchiha clan's reputation could take another hit. With Sasuke being divorced, there might be more speculation and gossip about the Uchiha family in the village. It could also affect Sarada, their daughter. She might have to deal with the stigma of her parents' divorce, which could be a major plot point in the fanfiction as she tries to come to terms with it and perhaps even tries to reunite her parents.
In a fanfiction where Naruko and Sasuke are married, it would affect the Naruto universe in many ways. Socially, it could break down some barriers between different clans. Since Naruko is from the Uzumaki clan and Sasuke from the Uchiha clan, their union would symbolize unity. This could lead to more inter - clan marriages in the future. In terms of the ninja world, their combined strength would be a major deterrent to any potential threats. And they could start a new ninja academy together, with a curriculum that focuses on both physical and emotional strength.
For their friends, it can be a huge shock. Naruto, for example, who has always been in the middle, trying to keep their relationship strong, might feel a sense of failure. Their other friends from the ninja teams might be divided in loyalty, some siding with Sasuke, some with Sakura. In the village, it could cause a scandal. The villagers might gossip and it could also affect the image of the Uchiha clan again, as Sasuke is part of it.
If Sakura and Pein were siblings, it could potentially change the power dynamics in the Naruto universe. For example, Sakura might be able to influence Pein's actions to some extent. She could try to persuade him to avoid attacking Konoha or at least reduce the destruction. This could also change the way the other characters in Konoha view her, as she would be related to one of their most dangerous enemies.
Naruto would be deeply saddened. He has always hoped for Sasuke and Sakura to be happy together. He might initially try to mediate and get them to work things out, believing that their relationship can be salvaged. He would remind them of the good times and how much they mean to each other.
The dynamic would be turned upside down. Sasuke would likely become more of an outcast or a loner, feeling rejected. Naruto would be in a difficult position, having to balance his friendship with Sasuke and his new relationship with Sakura. Sakura would be the catalyst for this change, and she would have to face the consequences of her actions, like dealing with the villagers' opinions and the potential backlash from Sasuke's supporters.
Taking care of Naruto might make Sakura more empathetic. She has to understand Naruto's pain and needs, which could make her a better ninja overall. As for Sasuke, it could break down some of his walls. He has to be vulnerable in front of Naruto and Sakura, showing that he's not just the aloof and brooding ninja. This experience might also make him more open to the idea of relying on others and being part of a team again.
One possible fanfiction could be about their baby inheriting Sasuke's Sharingan abilities. Maybe the baby shows early signs of these powers and Sakura has to figure out how to train the baby in both medical ninjutsu like her and also in the ways of the Uchiha clan. It could also show how Naruto interacts with the baby, being a close friend of Sasuke and Sakura. He might be like an uncle figure, teaching the baby some of his unique jutsu or life lessons.
It could strain the team dynamics. Naruto and Sasuke might feel suffocated by Sakura's possessiveness. Naruto, being the free - spirited one, might start to avoid Sakura if she's too overbearing. Sasuke, who values his independence, could also become distant. This would disrupt the harmony of the team that they had built over time.
The storyline would be greatly affected. In terms of character development, Naruto would have to learn a lot about Sakura, her insecurities, and her strengths. This new understanding could then be carried over when he turns back to his normal self. In the plot, it could also lead to new alliances or enemies. For example, if Naruto - as - Sakura accidentally offends someone who Sakura had a delicate relationship with, it could create new conflicts. Or, on the other hand, he could make new friends by showing a different side of Sakura that others hadn't seen before.
Well, Naruto has a very warm and persistent personality. He's always there for his friends, and he has a big heart. In fanfiction, Sakura might see these qualities in Naruto and realize his true value. He's the kind of person who can make her laugh and feel safe, which could be very appealing compared to Sasuke's more brooding nature.