He might meet some Disney princesses. They would be very different from the witches he knows in the wizarding world. Harry would probably be quite polite and respectful, as he is used to dealing with strong female characters. He could share stories of his adventures in Hogwarts with them.
Another character he could meet is Captain Jack Sparrow. Jack is a bit of a scoundrel, but also very charming. Harry might be a bit wary of him at first, but they could end up having an adventure together in Disneyland. Jack could show Harry some of the secrets of the pirate-themed areas of the park, and Harry could use his magic to help Jack out of a tight spot if they got into trouble.
There's a good chance he'd meet Mickey Mouse. Mickey is the face of Disneyland. Harry would be curious about this little mouse who seems to be so beloved by muggles. They might not be able to communicate directly at first, but Harry could use a spell to understand Mickey's squeaks. And Mickey would be fascinated by Harry's magic wand.
Well, Harry could use his magic to make the rides even more exciting. Maybe he'd use a spell to make the roller coasters fly higher or faster. He could also use his invisibility cloak to explore hidden parts of the park without being noticed.
He might meet Canadian witches and wizards. There could be a friendly wizard who shows him around the Canadian wizarding community.
He could meet new witches and wizards from different cultures. For example, he might run into a powerful African wizard who has unique magical abilities related to nature magic. Or he could meet a Japanese witch who specializes in charm - making that is based on ancient Shinto beliefs.
He might meet international aurors. These are highly skilled wizards from different countries who are experts in dark wizard catching. They could teach Harry some new combat spells.
He could meet Fleur Delacour's family. Since Fleur is from France, her family might be an important part of the French wizarding community that Harry interacts with.
He could meet his future children, if he has any. They would likely be powerful wizards or witches with their own adventures. Also, he might run into the future versions of Hermione and Ron. They would probably be in important positions in the wizarding world, like Hermione might be a headmistress at Hogwarts or something.
He might meet the future versions of his friends like Hermione and Ron. Their children or grandchildren could be there, and they might have different personalities and magical skills compared to their predecessors.
He might run into some of his old professors like McGonagall. She would be glad to see Harry back at Hogwarts. And perhaps he'll also meet some new students who look up to him as a hero. These new students could ask Harry for advice on how to be brave in the face of danger and how to master difficult magic spells.
Harry might meet some American wizarding families that have long - standing traditions different from the pure - blood families in the UK. These families could introduce Harry to new forms of magic and social norms within the American wizarding community. He could also meet American Muggle - born wizards who have their own unique stories of discovering magic in a different cultural context compared to what he's used to.
He could meet indigenous Canadian wizards who have their own unique magic traditions.