One common plotline could be that Hermione is betrayed by her friends in Hogwarts. For example, they might believe false rumors about her and turn their backs on her. Another could be a romantic betrayal, like if Ron, in a different take on the story, cheats on her or breaks her heart in some way. Sometimes, she could be betrayed by the wizarding community as a whole, perhaps being wrongly accused of dark magic and no one believing in her innocence.
Well, often in 'Hermione is betrayed' fanfictions, she's betrayed by authority figures. Maybe Dumbledore has a secret plan that involves using Hermione in a way she wouldn't approve of, and she feels betrayed when she discovers it. Or it could be that the Ministry of Magic turns on her. They might see her as a threat to their power because of her intelligence and progressive ideas. This can lead to her having to fight not only for her reputation but also for her safety.
One common plotline could be a character from Naruto being transported to the DxD world and feeling betrayed by the new characters they meet. For example, they might trust a devil at first but later find out they were being used for some dark purpose. Another plotline could involve a Naruto character's skills being exploited in the DxD world in a way that makes them feel betrayed by their own abilities. Maybe their power is harnessed in a way that goes against their moral code.
One common plotline is betrayal by a close friend. It could be someone from his village that he trusted, like a fellow ninja. They might reveal a secret or side with an enemy, making Naruto feel like he's been stabbed in the back.
In some fanfictions, the focus could be on Hermione's child's unique abilities or challenges. Since Hermione is very intelligent, her child might inherit her smarts but also have some special magical gift that she has to figure out how to handle on her own. Maybe the child has an uncontrollable power and Hermione has to search for ways to help the child manage it without a partner to support her. It could also involve her reconnecting with old friends from Hogwarts who either support or question her decisions as a single mother.
Often, there are plotlines centered around protecting Hermione. Since werewolves are sometimes seen as dangerous, the werewolf mate has to prove that he can keep Hermione safe, not only from the outside world but also from his own werewolf side during full moons. And there could be a plot where they work together to change the perception of werewolves in the wizarding society.
Often, there are plotlines where Hermione as a pureblood princess has special powers or abilities that come with her status. For example, she might have an innate magical ability that is unique to pureblood princesses in the fanfiction world. This could then be used to save the day in various situations, like fighting against dark wizards or solving complex magical mysteries.
One common plotline could be Hermione forming a closer friendship with Fleur. Since she hates Ron, she might turn to Fleur for support and they could end up having adventures together, perhaps in the wizarding world outside of Hogwarts.
One common plotline is the journey of Hermione and Ron (assuming she's married to Ron in the fanfic) as they prepare for the baby. It might involve them decorating the nursery, choosing baby names, and dealing with the excitement and nervousness of impending parenthood.
One common plotline is them trying to change the Slytherin house's negative image. They bring their Gryffindor values like bravery and loyalty into Slytherin and try to reform it from within. Another is their relationship with the other Slytherins. They might have to deal with the pure - blood supremacist ideas that some Slytherins hold. Some fanfictions also explore how they adapt to the Slytherin common room and its more secretive atmosphere.
One common plotline is Sirius being protective of Hermione. He might see her intelligence and bravery and feel drawn to her. He could protect her from various threats in the wizarding world, like Death Eaters or other dark forces.
Often, there could be a plotline where Snape helps Hermione with some sort of magical research, leading to a deeper understanding between them. Another common one might be Hermione getting into trouble and Snape being the unexpected savior.