She could have a secret identity as a time - traveling agent. In this fanfiction, Hermione discovers a way to time - travel without the use of a Time - Turner. She uses this ability to secretly correct historical mistakes in the wizarding world, all while keeping her identity hidden from her friends.
One idea could be that the child has unique magical abilities that neither Fred nor Hermione expected. Maybe the child can communicate with magical creatures in a way no one else can. Another plot could be the secrecy around the child's existence causing all sorts of misunderstandings among the Weasley family and Hermione's friends. For example, they might suspect Hermione of being involved in some dark magic when they notice her acting strangely to protect the secret.
A possible plot in this kind of fanfiction might be that Hermione starts tutoring Harry privately and during those sessions, their feelings for each other gradually surface. However, they keep it a secret because they are afraid of how Ron would react. This creates a lot of internal conflict for both of them. Harry might feel guilty towards Ron, and Hermione would be worried about breaking up the trio. Their love is a well - kept secret as they struggle with their emotions and the potential consequences.
One idea could be exploring what if Bruce Wayne's identity as Batman was exposed accidentally by a new high - tech surveillance system in Gotham. Another could be a story where Batman has to take on a new identity temporarily to infiltrate a secret criminal organization that has been studying his every move as Batman.
One interesting plot could be that Naruto has a secret identity as a powerful shadow assassin. In this fanfiction, he uses this identity to take on dangerous missions that the village can't officially support. Another plot might be that his secret identity is that of a diplomat from a far - off land, which he uses to gather intelligence for Konoha without being detected as a shinobi.
You could create a fanfiction where the main character discovers a new, hidden part of Moonacre that was never mentioned in the original story. Maybe it's a magical garden that holds the key to an even greater mystery. This would add a new layer of adventure and intrigue.
A crossover with a fairy - tale world would be cool. Imagine the survivors and hunters in a twisted version of 'Alice in Wonderland'. The survivors might have to navigate through the strange and dangerous Wonderland while being chased by the hunters, who could be some of the more menacing Wonderland creatures.
Another plot could be Hermione changing her identity because she is wrongly accused of a crime. She decides to assume a new identity to clear her name. In this new identity, she travels to different magical communities, looking for evidence that can prove her innocence. Along the way, she meets new characters and has various adventures.
One idea could be that Hermione discovers she has a special connection to the gorgon world. Maybe she can understand their language and has to use this ability to prevent a war between the gorgons and the wizarding world. Another plot could involve Hermione being turned into a gorgon - like creature temporarily and having to learn to control her new powers while facing prejudice from some of her classmates.
Another plot could be that Hermione, being the brilliant witch she is, gets sorted into Hufflepuff by mistake (or maybe it's not a mistake). She initially struggles with the idea as she has always identified more with Gryffindor. But as she spends time in Hufflepuff, she realizes that the house values are just as important and noble. She then uses her intelligence to help Hufflepuff gain more recognition in the wizarding community.
One plot idea could be that Hermione, through some magical accident, is transported back in time and meets a young Gellert Grindelwald. She tries to use her knowledge to change his path towards dark magic. Another could be a story where Gellert, in his prison at Nurmengard, has visions of Hermione and they communicate magically across time. A third idea is that in an alternate universe, Hermione is a student at Durmstrang and becomes influenced by Gellert's ideas, but then has to decide whether to follow his dark path or her own moral compass.