In some fanfictions, it could be that Harry has a vision or a dream about how to heal Neville's parents. He then seeks the help of some of the most brilliant minds at Hogwarts, like Professor McGonagall and Hermione. They work together to create a potion based on Harry's description from the vision. Harry then administers the potion to Neville's parents and with the combined power of the potion and Harry's Gryffindor - like courage and magic, they start to regain their sanity and health.
One possible plotline could be that Harry discovers a long - forgotten spell in an ancient book in the Room of Requirement. He spends days researching and practicing it in secret. Once he masters it, he approaches Neville and tells him about his plan. They then go to St. Mungo's together and Harry performs the spell. At first, it seems like nothing is happening, but slowly, Neville's parents start to show signs of recognition and recovery.
Neville would become more confident. Knowing that his parents are healed, he no longer has that underlying pain and worry. He would be more assertive in his actions and decisions, and might even take on more leadership roles at Hogwarts or in the wizarding world in general. For example, he could be more outspoken in the DA meetings.
One possible plotline could be Harry feeling extremely lost and alone at first. He might have to find a new place to live, perhaps with the help of his friends like Ron and Hermione. He could struggle with self - worth, constantly wondering what he did wrong to make his parents disown him.
In fanfiction, when Harry and Neville meet their parents, it could be an extremely emotional encounter. Harry might finally get the chance to know his parents as the loving individuals they were, not just the tragic figures from his past. He could ask them all the questions he's had about his family history. Neville, on the other hand, might find strength and validation from his parents. They could offer him advice on how to be brave in the face of the challenges that lie ahead. It could also be a moment of great healing for both of them, filling in the voids of parental love they've had in their lives.
Maybe Hermione is injured while exploring some dangerous magical ruins. Snape is the only one around with the knowledge and power to heal her. As he heals her, they start to have deep conversations about magic, life, and their respective pasts, which in turn builds a connection between them.
One possible plotline could be Naruto exploring his parents' memories in the mindscape. He might discover secrets about their past, like how they met or their early days as shinobi. For example, he could find out about his father's training and how his mother came to be a jinchuriki. This could lead to Naruto gaining new powers or a deeper understanding of his heritage.
Another plot could involve a sort of magical exchange. Orochimaru, being a master of some dark and strange jutsu in his own world, might offer to teach some of his knowledge to certain dark wizards in the Harry Potter world in exchange for something valuable. Harry Potter and his friends would have to prevent this knowledge transfer as it could tip the balance of power towards the dark side in their world. They might need to seek help from some of the more powerful and wise wizards like Dumbledore to outwit Orochimaru.
Another plot could involve Medusa being a part of a long - forgotten magical mystery that is somehow related to Harry's destiny. Harry, with his inquisitive nature, starts to research about her. As he gets closer to the truth, he has to face the danger of being turned to stone. But through his courage and the help of his friends, he manages to break the curse on Medusa, and in return, she helps him in his fight against Voldemort.
One possible plotline could be that Harry betrays Draco in a duel. Maybe there was some sort of misunderstanding or a secret deal that Harry made with someone else that required him to turn on Draco during the duel. For example, if there was a dark wizard threatening Harry's friends and the only way to save them was to sacrifice Draco in the duel by using a forbidden spell against him.
One possible plotline could be that they are researching a very difficult and dangerous dark magic that is starting to surface in Hogwarts. They are in the library trying to find clues in old books to stop it before it causes harm. They might discover a hidden prophecy related to it.
One possible plotline could be Snape finding drunk Harry in the Hogwarts corridors. Snape, being the strict teacher, might initially be angry but then realizes Harry is in a vulnerable state. He could take Harry to his office to sober him up and in the process, they have a conversation that reveals some hidden feelings or understanding between them.