Perhaps he would find that the wizarding world has finally united with the Muggle world in harmony. Technology in the Muggle world could have influenced magic in strange and wonderful ways. He could be shocked to see flying cars that are now common, or houses that are built with a combination of magic and advanced Muggle construction techniques.
In this fanfiction, Harry might see a world where magic has evolved in ways he couldn't imagine. Maybe there are new spells and potions that are far more advanced. He could also encounter the future versions of his friends and enemies. For example, he might find out that Ron has become a very important figure in the wizarding world, or that Voldemort's influence still lingers in some unexpected ways.
Well, he might see some amazing technological advancements. Maybe flying cars are everywhere and houses can move. He could also meet his descendants and see how his family has grown over the years.
Well, Harry could be really confused at first. Ouran is a very different world from Hogwarts. He might be shocked by the opulence of Ouran Academy and the strange club system there. Maybe he'd try to find a way to fit in while still being true to his wizard self.
Maybe Harry has some strange magical illness that normal wizards can't cure. So he has to seek help from a very special doctor who might have some unique remedies.
Perhaps he would be seen as an oddity at Alfea. After all, he comes from a completely different magical system. But his reputation as the 'Boy Who Lived' might precede him. Some might be in awe of him, while others might be skeptical. His presence could also stir up some rivalries among the students at Alfea who are used to their own hierarchies. Harry would have to find his place among the fairies and deal with any potential jealousies or hostilities.
Well, he might encounter new magical creatures unique to America, like the Thunderbird. He could also visit American wizarding schools and be amazed by their different teaching methods compared to Hogwarts.
In this fanfiction, Harry could attend a Canadian wizarding school. He'd have to adapt to a different teaching style and make new friends. The curriculum might include courses on Canadian magical history and spells that are specific to the region. He might also face some challenges from local wizards who are not used to having a famous wizard like him around.
Well, in this fanfiction, Harry Potter might face new magical challenges in the ICW (International Confederation of Wizards). He could encounter different magical cultures and spells from around the world. Maybe he'll make new friends or enemies among international wizards.
Well, he might visit Beauxbatons Academy. Maybe he would meet some new friends there, like some interesting French wizards or witches. He could also explore the French wizarding culture, which is likely different from what he's used to in England.
His Gryffindor courage would still be put to the test. There could be difficult exams and challenges at college. He might also get involved in some sort of college - wide magical competition. And he would have to balance his social life, his studies, and any potential threats from the dark magic side that still exists.