One idea could be Snape using the Time - Turner to go back and change a crucial moment in his relationship with Lily. Maybe he tries to prevent her from getting involved with James Potter. Another plot could involve Snape using it to gain an edge in his spying for Dumbledore during the First Wizarding War. He could go back in time to gather more information about Voldemort's early plans.
Well, a really interesting plot could be that Snape discovers a hidden power of the Time - Turner. He might find out that it can not only take him back in time but also to alternate timelines. So he travels to a timeline where Voldemort never existed. There, he sees how different the wizarding world is and then has to decide whether to bring back some of those positive changes to his own timeline or leave it as it is for fear of unforeseen consequences.
A great plot might be Snape going back in time to his own Hogwarts days and trying to correct some of the mistakes he made that led to his bad reputation. He could use the Time - Turner to befriend more people or study harder in certain subjects. Also, perhaps he uses it to change how he was treated by the Marauders. For example, he could figure out a way to stop their constant bullying.
One idea could be that Hermione accidentally travels too far back in time with the Time - Turner and ends up in Severus' student days. She has to navigate Hogwarts without being detected while also trying to figure out how to get back. And Severus stumbles upon her and at first is suspicious but then realizes she's from the future and they start to work together to fix the time - line.
Snape would have more opportunities to right his wrongs. For example, he could go back and be more honest with Lily about his feelings. His character could become less bitter as he gets a chance to change things that made him so resentful in the first place.
One idea could be a time - travel plot where Hermione goes back in time and has to work with a younger Severus Snape. They could team up to prevent a dark wizard from rising earlier than in the original timeline. This would put them in a situation where they have to trust each other despite their differences in age and temperament.
Well, we could have a fanfiction where Snape is alone after the war. He's left to pick up the pieces of his life. He decides to go on a journey to find a place where he can truly be at peace. Along the way, he meets some muggles who unknowingly teach him about the simplicity of life. This makes him realize that he doesn't need all the magical trappings to be happy.
One idea could be that Snape takes Malfoy under his wing in a more personal way than just as a student. Maybe he discovers Malfoy's hidden talents in potions that no one else has noticed and helps him develop them further. This could lead to a bond between them that goes against the typical Slytherin hierarchy.
One idea could be a time - travel plot. Snape goes back in time to change the events that led to Lily's death. He tries to prevent Voldemort from targeting the Potters. This would involve a lot of interaction with his younger self and trying to navigate the past without changing too much.
Another plot idea could be that Snape's skills as a potion - maker are seen in a different light as a girl. She might be underestimated more often at first, but then she uses her skills to gain respect in a more unexpected way, like creating a potion that helps solve a mystery in Hogwarts.
Well, a plot could be that there is a mystery in Hogwarts that only Snape and Hermione seem to notice. They start investigating together, initially distrusting each other. As they dig deeper, they find that it is related to a long - forgotten potion recipe. Along the way, they have to face challenges like avoiding other teachers' suspicions and dealing with some magical creatures that are guarding parts of the mystery. Another interesting plot could be that Snape and Hermione are magically linked in some way, perhaps due to a spell gone wrong. They start experiencing each other's emotions and memories, which forces them to understand each other on a much deeper level. This could lead to a whole new relationship between them, different from the typical student - teacher dynamic.
One idea could be that Snape's portrait has the ability to communicate with the living not just in the castle, but also with those who were once his students far away. It could offer guidance to Harry Potter's children, sharing secrets about the past and how to handle the new threats in the wizarding world.
One idea could be exploring Snape's family history as a pureblood. Maybe he discovers a long - lost family secret that has been hidden for generations. Another could be a story where Snape has to navigate the pureblood society's expectations while still being true to his own beliefs and loyalties.