In a 'Harry Potter Justice League crossover fanfiction', there would be a lot of interesting interactions. The wizards from Hogwarts and the superheroes of the Justice League would have to figure out how to work together. For example, Batman would be intrigued by the magic of Hogwarts and might try to analyze it scientifically. At the same time, Hermione could learn a thing or two from Batman's detective skills. And when it comes to facing a common enemy, like an alien sorcerer, they would combine their powers. The Flash could use his speed to quickly deliver magical items that the wizards need in battle, while the wizards use spells to protect the Flash from magical attacks.
Well, I think Batman and Hermione could be main characters. Batman's intelligence and detective skills combined with Hermione's vast knowledge of magic would make for an interesting dynamic. They could be the ones leading the team in strategizing against the common enemies that the crossover would bring. Also, Wonder Woman and Ginny Weasley could be important. Wonder Woman's strength and combat skills paired with Ginny's talent in magic, especially her Bat - Bogey Hex, could make them a formidable duo in the story.
One idea could be that Voldemort discovers a way to enter the DC universe and teams up with some of the Justice League's villains like Lex Luthor. The Hogwarts students and the remaining members of the Justice League have to join forces to stop them. The wizards can use their magic while the superheroes use their powers.
Yes, there are quite a few. You can start by looking on fanfiction websites like Archive of Our Own or FanFiction.net. Just search for the key terms 'Harry Potter Justice League Harem' and you'll likely find some interesting reads. However, the quality can vary greatly, so it might take some time to find one that really suits your taste.
One idea could be that Tsunade is brought to the Justice League's universe through some sort of magical portal mishap. She could use her medical ninjutsu skills to help treat injured Justice League members, like when Superman gets hurt by a kryptonite - based weapon. Her tough - as - nails attitude would also make for some interesting interactions with Batman, who might be intrigued by her no - nonsense approach.
Another concept is that the magic from the Harry Potter series starts to seep into the DC universe where the Justice League operates. This causes chaos as the laws of physics in the DC world are disrupted. The Justice League has to seek help from Hogwarts professors to understand and contain this new form of magic energy. Superman might be intrigued by the idea of magic being a new power source or a new threat he can't easily overcome with his super strength.
One way it could work is by having the magical elements of Harry Potter in the Justice League universe. For example, the wizards could help the Justice League with their spells in battles against powerful foes. Maybe Harry Potter himself could use his Patronus charm to fend off some of the League's enemies like Darkseid's minions.
It could be a wild adventure where Harry Potter, with his magical abilities, teams up with the Justice League. Maybe Harry uses his spells to enhance the League's powers or to combat enemies that are immune to their usual tactics. For example, he could use a Patronus charm to fend off some dark, mind - controlling villains that the League has trouble with.
Well, in a fanfiction where Harry Potter joins the Justice League, there would be some interesting interactions. Harry's knowledge of the magical world could help the Justice League deal with threats that have a magical or otherworldly origin. His experience in fighting dark wizards might give the team new strategies. Also, the members of the Justice League would probably be fascinated by his magic, and there could be some funny moments of them trying to understand how it all works.
A really cool crossover concept could be a combined threat that requires both the skills of the Justice League and the magic of the Harry Potter world to defeat. Maybe a powerful alien sorcerer arrives on Earth. The Justice League's superpowers alone aren't enough, so they team up with Harry Potter and his friends. Harry could use the Patronus charm to fend off the dark magic of the alien, while the Flash could use his speed to quickly deliver magic items to different locations as needed.