Another scenario is that their meeting could be a very brief and mysterious one. It could be a chance encounter in a magical place, like a wizarding market. They exchange a few words, but it leaves a lasting impression on both of them. Later, when they meet at Hogwarts, they feel a sense of deja vu and start to explore the connection they had from that initial meeting.
Well, one possibility is that they could form an early friendship. Maybe Fleur, with her Veela charm, would initially intimidate Harry, but then they find common ground in their magical abilities. For example, they might discover they both have an affinity for certain types of magic that are not common among their peers. This could lead to them sharing magical secrets and techniques before even reaching Hogwarts.
If there was a rivalry before Hogwarts, it could carry over and make their interactions at Hogwarts more tense. However, this could also lead to them pushing each other to be better. For example, in Quidditch, if Fleur is also a good flyer, Harry might strive to outperform her, which could improve his skills as a Seeker. And over time, this rivalry might turn into mutual respect.
One possibility is that they form an instant friendship. Maybe they discover they have a shared interest in magic even before getting their Hogwarts letters. For example, they might both have had strange experiences with objects moving on their own, and this commonality draws them together.
Well, they might start a family right away. In some fanfictions, they get married quickly and have a bunch of kids. They could also go on adventures together, exploring the wizarding world outside of Hogwarts.
In the 'hogwarts meets the future fanfiction', there could be a great exchange of knowledge. The Hogwarts students could learn about future sciences like advanced astronomy or genetics, while the future people could be amazed by the magic of Hogwarts. There might be a character from Hogwarts who becomes a bridge between the two worlds, teaching future people about magic and in turn learning about their advanced technologies.
Well, they might discover their shared love for magic right away. Maybe they find some strange magical creature together and start to figure out how to take care of it. This could be a start of their magical adventures even before Hogwarts.
Fleur could become an ambassador between the wizarding communities of Britain and France. Harry, having a great reputation, could support her in this role by being a symbol of unity. He might also write books about his experiences, which could be used in magical schools as a way to teach about the importance of fighting against evil. In this way, they both have careers that are intertwined with the betterment of the wizarding world.
One possible plot could be that they meet during a wizarding event in France. Fleur, being from a French wizarding family, might be at a magical fair. Harry could be there with the Dursleys on a 'family' trip (forced by the Dursleys to go to France). They accidentally cross paths and Fleur, sensing Harry's unique magical aura, strikes up a conversation. This could be the start of an interesting pre - Hogwarts friendship.
It's also likely that Harry, having faced so much darkness, decides to take a break from the wizarding world for a while. Fleur, on the other hand, is still very much involved in the magical community. She might persuade Harry to come back and they start to explore different magical cultures together. They could travel to far - flung places, discover new spells and magical creatures, and in the process, their relationship blossoms.
Their meeting could also mean that Fleur might be more protective of Harry at Hogwarts. Since she knew him before, she might feel a sense of responsibility. So, during the Tournament, she could offer him some tips or help in a more discreet way, which could change the dynamics of how the Tournament unfolds for Harry.
They could meet in Diagon Alley. Harry is new to the wizarding world and is just in awe of everything. Ron, on the other hand, has been there before. Ron spots Harry looking at a wand in Ollivander's shop. He goes over and starts sharing his own experience of getting his wand. They then walk around Diagon Alley together, looking at all the magical creatures and items. This meeting would give Harry a sense of belonging in the wizarding world and make Ron feel important as he gets to show off his knowledge.