Harry and Ron are the most obvious choices. They've always been there for Hermione in the original series, so it would make sense for them to be the ones to find her and try to save her life. They would use their combined magical skills and knowledge to fight off any remaining threats and get her to safety.
It could be Neville. He has grown into a very powerful wizard. He might stumble upon Hermione while on his own adventure or while out exploring the grounds. Neville has a strong sense of justice and loyalty, so he would definitely do everything he could to save her. He could use his knowledge of herbology to find healing plants to help her.
Another potential savior could be a new character introduced in the fanfiction. Maybe a powerful healer from a far - off land who has a special connection to Hermione's magic. This character could sense her distress and come to her rescue, using unique healing spells and potions that are not known in the wizarding world of Hogwarts.
It could be Death Eaters who see Hermione as a threat to their new plans. Since she's very intelligent and has been involved in many battles against the dark side, they might target her to send a message to the Order of the Phoenix.
In some fanfictions, Hermione could be attacked by a new, unknown magical creature that has been unleashed by an evil force. She might be left for dead because the attacker believes she is already dead or simply doesn't care. It could also be that she is betrayed by someone she trusts, like a fellow Hogwarts student who has turned to the dark side, and they set her up to be attacked.
One possible plotline could be that Hermione was attacked by a group of dark wizards while on a solo mission. They might have been after some knowledge she possessed. After the attack, she could be found by a mysterious figure who nurses her back to health and together they seek revenge.
Perhaps an older teacher or coach who has always had an eye on Kuroko's potential could step in as a savior. They could see the signs of bullying and use their authority to punish the bullies and provide support and guidance to Kuroko, helping him to grow stronger both on and off the court.
Hermione could be a potential savior. She's smart and resourceful. She might figure out where Lockhart has taken Harry by using her vast knowledge of magic and Hogwarts' secrets.
A new student in the school could be the one to save Sakura. This new student might have had similar experiences in their previous school and decides to take a stand against the bullies when they see Sakura being harassed.
Dumbledore could be a savior in this fanfiction. He has the power and the wisdom to step in and help Harry. He might have been waiting for the right moment to remove Harry from the Dursleys' influence. Also, there could be a new character, like an old and powerful wizard who has been in hiding but senses Harry's distress and comes to his aid. This wizard could have some unique magical abilities that can protect Harry and help him grow into a powerful wizard himself.
A wandering samurai could be his savior. This samurai, having a strong sense of justice, stumbles upon the baby Naruto. He takes Naruto under his wing and teaches him swordsmanship and a different code of honor. Naruto grows up with a unique set of skills and a different perspective on life compared to if he had been raised in the village.
His friends from Camp Half - Blood, like Annabeth, Grover, and Tyson, could be the potential saviors. They have always been by his side and would do anything to rescue him.
Kakashi could also play a role. He has always been a mentor to Naruto and his sense of duty and loyalty to his student might drive him to search for Naruto when he hears that he's been left for dead. He has the skills and knowledge to find and save Naruto in a difficult situation.