Well, perhaps in the fanfiction, Hermione as a Veela has the ability to enter Tom Riddle's dreams. In his dreams, she shows him the consequences of his future actions as Voldemort. This makes Tom start to have doubts about his planned path of evil, and he has an internal struggle between his dark desires and the newfound influence of Hermione's Veela presence.
One plot idea could be that Hermione travels back in time and tries to prevent Tom Riddle Jr from becoming Voldemort. She might use her knowledge and magic skills to change his path. Another could be a scenario where they meet in an alternate universe where the rules of good and evil are more blurred, and they form an unlikely alliance to face a greater threat. Maybe Hermione gets trapped in a magically created world by Tom Riddle Jr, and she has to outwit him to escape and in the process, she discovers some hidden secrets about his past that could have changed his future.
Well, perhaps in the fanfiction, Hermione time - travels to Tom Riddle's era and she attempts to understand his early life better. She could try to find the root of his evil and change it. For example, she might discover that a particular event in his childhood was the turning point. As for Tom Riddle traveling to Hermione's time, he could be fascinated by the advanced magic and the different social structure in the wizarding world, which might make him question his own beliefs.
One plot idea could be that it's a time - travel based fanfic. Hermione somehow gets sent back in time and meets Tom Riddle before he fully turns into Voldemort. Their relationship starts out as a strange sort of intellectual connection. Maybe she tries to prevent him from going down the dark path and in the process, they develop feelings for each other which leads to her getting pregnant. This could then create a whole new timeline where the wizarding world is different due to Tom's change of heart.
At first, their relationship would be filled with conflict. Hermione, as a Veela, would have strong moral values which would clash with Tom's budding dark tendencies. However, as the story progresses, her Veela charm could slowly break down his defenses. He might start to open up to her, and they could develop a complex relationship where they both influence each other in different ways.
Another possibility is a scenario where Hermione is on a mission to study the early life of Voldemort for some academic or magical research. While at the orphanage, she discovers some hidden secrets about Tom Riddle's family that were previously unknown. This could lead to a series of events where she has to protect this knowledge from falling into the wrong hands, all while interacting with a young and curious Tom Riddle.
One idea could be a time - travel fanfic where Harry goes back in time and tries to prevent Tom Riddle from becoming Voldemort. He could try to befriend the young Tom and show him a different path. Another could be a fanfic where Harry and Tom are somehow trapped in an alternate dimension together and have to work together to escape, all while Harry tries to understand what made Tom turn so evil. A third idea is a fanfic where Tom Riddle actually has a change of heart early on due to some magical accident that makes him experience a different kind of love and kindness, and Harry has to deal with this new Tom in Hogwarts.
One plot idea could be that Fem Harry, with her unique perspective as a female in a male - dominated wizarding world, catches Tom Riddle's attention in Hogwarts. He's intrigued by her different way of approaching magic. Maybe she's more empathetic and uses magic in a way that he's never seen before, leading to a complex relationship where he both admires and is jealous of her power.
In some fanfictions, Tom Riddle and Hermione are paired in a situation where they have to work together to solve a great mystery at Hogwarts. Maybe it's a mystery that dates back to the time when the founders were there. Hermione's modern knowledge of magic combined with Tom Riddle's old - school understanding could create an interesting dynamic. There are also fanfictions where Hermione is sent to an alternate reality where Tom Riddle has already become Voldemort but she tries to find a way to change his fate by getting to know the human side of him that still exists deep within.
One idea could be that in the orphanage, Tom discovers a hidden magical ability within Hermione that she was unaware of. Maybe they team up to face a mysterious threat that is targeting the orphans. This could lead to them exploring the secrets of the orphanage together.
One plot idea could be a time - travel scenario where Harry goes back in time and meets a young Tom Riddle. He tries to change Tom's path to prevent him from becoming Voldemort. Another could be a situation where they are magically bound together and have to learn to co - exist and understand each other's motives.