One way could be that Godzilla somehow appears in the wizarding world. Maybe a magical experiment goes wrong and transports Godzilla there. Then the wizards and witches have to figure out how to stop it using magic.
Well, the plot could start with a mysterious portal opening near Hogwarts and out comes Godzilla. The students and professors are terrified. Harry, Hermione, and Ron could then start researching ancient spells that might be able to either send Godzilla back or at least subdue him. There could also be a sub - plot where some dark wizards try to control Godzilla for their own evil purposes. The story could be full of action as the characters race against time to deal with this giant threat in their magical homeland.
One way could be that Harry is somehow transformed into a RoboCop - like figure in the wizarding world. He could use his new robotic powers along with his magic to fight against dark wizards. For example, his robotic enhancements could give him super strength to physically combat opponents, while his magic could be used for more complex spells.
Well, one possibility could be that Godzilla somehow ends up in the wizarding world. Maybe a powerful dark magic spell goes wrong and creates a portal that sucks Godzilla in. Harry and his friends at first think it's a new kind of dark creature created by Voldemort. They try to fight it using spells, but soon realize that Godzilla is not exactly evil. Godzilla might then start causing destruction in Hogwarts, and the wizards have to figure out a way to either send it back or control it without killing it.
One way it could work is by having Harry Potter be transported to the world of Noctis. He could use his magic skills there and face new challenges that are different from what he's used to in Hogwarts. For example, the magic in Noctis' world might be more elemental - based, and Harry has to adapt to use his wand magic in that context.
The plot could start with Harry having strange dreams about Shinigami. As he investigates, he discovers that there is a hidden portal in Hogwarts that leads to a realm where Shinigami exist. He and his friends enter this realm, and they find out that there is a dark force in the wizarding world that is related to the Shinigami in some way. They then have to work with some friendly Shinigami to stop this dark force. Along the way, they learn about new forms of magic and the true nature of death from the Shinigami.
The plot could start with a spell gone wrong in Hogwarts that somehow transports a group of Transformers to the wizarding world. The wizards are initially scared but soon realize that they need to cooperate with the Transformers to deal with a new dark force that is attracted to the combination of magic and technology. The story could involve battles, magic - tech hybrids, and new friendships between the two groups.
One way could be to have Harry be adopted by a Mandalorian family. He grows up learning both magic and Mandalorian combat skills. Then, he has to use his combined knowledge to fight against a common enemy that threatens both the wizarding world and Mandalore.
One way it could work is by having Harry Potter be a secret admirer of Gomez Addams' unique style and way of life. Maybe Harry discovers some old wizarding texts that mention a connection to the Addams family's magic. He then becomes fascinated and starts to incorporate some of Gomez's traits into his own life, creating an interesting blend of the two worlds.
It could entail Harry having the powers of a dovahkiin. So he might be able to shout like a dragon and have enhanced physical abilities. He could use these powers to fight Voldemort in a completely different way, perhaps using dragon shouts to disarm or stun death eaters.
Potentially, it could be about Harry's destiny as a guardian of the balance between the magical and non - magical worlds. He might discover that he has a role to play in preventing the two worlds from colliding in a disastrous way. So he has to take on this new identity as a guardian, which involves making difficult choices, facing new challenges, and forging new relationships with both wizards and non - wizards.
It could be about Harry Potter somehow ending up in Halloween Town where Jack Skellington rules. Maybe Harry has to use his magic to help Jack with some sort of problem in Halloween Town, like a dark magic that is threatening to overtake the town.