Hermione would likely approach Tom's dark past with a great deal of research. She'd probably dig into the history of Voldemort's early years to understand what led him down that path in the first place. By knowing the root causes, she could try to prevent the same things from happening to Tom. For example, if she found out that loneliness and a sense of being an outcast were factors, she'd make sure Tom had a strong support system at Hogwarts.
She would face the challenge of dealing with Tom's own nature. Even as a baby, he might have some of the traits that later led to his dark side. Hermione would have to find ways to nurture his good side and suppress the bad. Also, she has her own life and studies. Balancing taking care of a baby and her own development would be difficult.
One possible plot twist could be that Tom Riddle's dark tendencies start to resurface despite Hermione's positive influence. Maybe he begins to secretly manipulate those around him at Hogwarts while still maintaining a facade of being a reformed child. This could lead to a rift between Hermione and some of her friends who suspect Tom but don't understand why Hermione is so trusting.
The story could also involve Hermione using her magical knowledge to help Tom control his powers. Since Tom is a powerful wizard from a young age, he might have difficulty handling his magic properly. Hermione, being a brilliant witch, could guide him. This could lead to a unique bond between them, where Tom respects Hermione for her abilities and Hermione sees the potential for good in Tom.
If Hermione adopts Tom Riddle, it could potentially prevent the rise of Voldemort. This would mean a much more peaceful wizarding world. There would be no First or Second Wizarding Wars, and countless lives would be saved. Families like the Potters and the Weasleys would not have to endure the pain and loss they suffered in the original timeline.
I really liked 'My Adopted Son, Tom Riddle'. This fanfiction has a unique take on the idea. The reader not only adopts Tom but also tries to shield him from the dark influences at Hogwarts. It has some great plot twists and the writing style is very immersive.
It would change the future of the wizarding world a great deal. Hermione is a smart and kind - hearted witch. With her as Tom's mother figure, she would likely encourage his academic pursuits in a positive way. He might grow up to be a great wizard who uses his powers for good instead of evil, thus changing the whole power dynamic in the wizarding world.
A fanfiction titled 'Hermione's Refuge' has Remus adopting an abused Hermione. This story is unique as it not only focuses on Hermione's recovery but also on how Remus has to face the wizarding community's reactions. It shows that their relationship is not without challenges, but through it all, they support each other.
In such a fanfiction, Sirius might have to face various challenges while adopting Hermione. For example, there could be opposition from some parts of the wizarding community who might question his motives or his ability to take care of her. However, Sirius, with his strong will and love for Hermione, overcomes these obstacles. He might also help Hermione develop her magic skills further and give her the confidence she lacks due to the abuse she has endured.
One great fanfiction with this concept is 'A New Beginning'. In it, Narcissa discovers Hermione's situation and decides to take her in. It beautifully shows Hermione's adjustment to living with the Malfoys and how Narcissa protects her from further harm. It also delves into the complex relationships within the wizarding world and how Hermione's presence changes things for the better in the Malfoy household.