A possible plot for a baby Harry Potter and Hermione Granger fanfic could be that they are both sent forward in time as babies to a future where Voldemort has won. They grow up in this dark world and have to rely on their natural magical talents and their friendship to start a resistance. They might discover new forms of magic that were lost in the past and use these to their advantage. Maybe they find a way to communicate with the past versions of their parents and friends to get help. It would be a story of hope and the power of friendship even in the darkest of times.
One idea could be a story where baby Harry and Hermione are magically transported to a different time or place. They could be in a magical forest full of strange creatures that they have to befriend in order to find their way back. Another plot could involve them as babies having a special connection that allows them to communicate without speaking. This could lead to them solving small mysteries in Hogwarts even at a very young age. A third idea might be that they are found by a group of magical beings who don't know who they are and raise them with different magical traditions, and later they discover their true identities.
One idea could be a time - travel fanfic where Harry and Hermione go back in time to change certain events in the wizarding world's history. This could lead to all sorts of interesting plot twists.
Another plot could be that the baby's existence somehow threatens the balance of power in the wizarding world. Some dark forces might want to use or harm the baby for their own gain. Harry and Hermione then have to fight against these forces, all while raising their baby in a world full of danger and intrigue.
One idea could be that after a major battle, Hermione realizes that she and Harry have grown in different directions. She decides to break their friendship in order to pursue her own path of magical research. This could lead to a story where Harry initially feels betrayed but then comes to understand Hermione's decision as he too embarks on his own journey of self - discovery.
One idea could be that during detention, Hermione discovers a hidden magical artifact in the classroom. This leads to an adventure where she has to figure out its purpose and keep it safe from those who might misuse it.
One plot idea could be that Hermione, through some magical mishap, ends up in the Marvel universe and meets Steve Rogers. She could use her magic to help the Avengers in a battle against a powerful enemy that their technology can't handle. For example, she might use a spell to contain a powerful energy source that was about to explode and destroy a city.
A plot where Snape, after his supposed death, is brought back in a way and Hermione discovers him. She then has to help him regain his strength and memories. Along the way, they form an unlikely friendship and explore the secrets of magic that Snape had been researching before his death. It could involve Hermione seeing a different side of Snape than she ever expected.
She might be a maid at a magical inn. Hermione could encounter all sorts of strange wizards and witches as she cleans their rooms. She could stumble upon a mysterious object left behind by a guest and then begin a quest to figure out what it is and where it belongs, using her vast knowledge of magic.
The plot could be that a mysterious collar is found in the Forbidden Forest. Hermione, being curious, examines it and accidentally activates it. The collar then starts to affect her magic in strange ways. Harry has to help her figure out how to remove it while also dealing with threats from dark forces who are interested in the collar's power.
Well, a plot could involve the baby boy being a huge Harry Potter fan in a world where magic is real but not as well - known as in the books. The daddy, who doesn't believe in magic at first, is then drawn into the magical world because of his son. They could go on adventures to find hidden magical places, similar to the places Harry and his friends discover in Hogwarts.
It could be a new dark wizard. Maybe a jealous former Hogwarts student who felt overshadowed by Dumbledore and now sees baby Harry and Hermione as threats to his future plans. He might want to use their power for himself or just eliminate them to make sure he can rise to power unopposed.