To her rivals, it could be an opportunity. They might see her leaving as a sign of weakness or as a chance to gain more influence in the village. But on the other hand, some of them might also be secretly worried that she would return one day much stronger than them, which could change the power dynamics in the village.
For her friends, it could be a shock. They might feel betrayed, especially if she left without much explanation. Her best friend might feel sad and lonely, constantly wondering why she left and if she would ever come back.
In some fanfictions, she might leave to fulfill a prophecy or a special mission. There could be an ancient prophecy that only she could fulfill, and it required her to leave the village at that young age. She might have been guided by some mysterious force or a vision that she believed was leading her towards her destiny.
The village might have lost a potential future asset. If Sakura had shown any signs of great potential at that young age, her leaving could be a blow to the village's future prospects.
Percy's leaving could also have an impact on the family's reputation in some fanfictions. People in the wizarding community might start to gossip, which could put additional pressure on the Weasley family. And some characters outside the family, like Harry, might feel a sense of loss as Percy was also part of his extended circle. He might try to mediate between Percy and the rest of the Weasley family if he gets the chance.
For the other members of the Bat - family, like Dick Grayson or Barbara Gordon, it could create a rift. They might be caught in the middle between Tim and Batman. They may also start to reevaluate their own positions in the Bat - family, wondering if they too should consider leaving or changing their roles.
Sakura's regret could lead to her making amends. She might start doing things to show Naruto she's sorry, like helping him in his missions or protecting him. This changes the power dynamics between them and also affects how other characters interact with them, as they all witness this shift in their relationship.
Well, their relationship with Sakura could become more strained. Since they left, she might feel abandoned and angry at them at first. But later, she could also come to understand their reasons. With Kakashi, he might be disappointed in them for leaving, but also secretly hope they find their own path. As for their enemies outside the village, they might start to see Naruto and Sasuke as more of a threat since they are no longer bound by the village's rules.
The other young members like Robin (if there's a new one) or Batgirl could be affected in terms of their own development. They might start to wonder if they should also consider leaving at some point. And it could create a sense of instability within the group as they have to adjust to not having Tim around.
For Blake, it could be a huge relief. Adam was a source of great stress and fear for her. His leaving might give her a chance to fully break away from her past traumas related to him and the White Fang. She can focus more on her own growth and her relationships with Team RWBY.
Kakashi would be deeply affected. He has mentored both Sasuke and Sakura. This would make him question his own teachings and his ability to protect his students. He might also feel a sense of responsibility and could become more involved in trying to bring Sasuke to justice or at least understand what drove him to such an extreme act.
For Hermione, it would be a huge blow. She would likely feel a great sense of guilt, thinking she could have done more to prevent it. She might become more withdrawn and throw herself into her studies even more, but also be haunted by memories of Harry. Ron would be devastated too. He might lose his sense of humor for a while and become more serious. He would also be very angry, perhaps vowing revenge if Harry was killed by someone.