Hermione would likely be a key friend. She might be initially very confused and try to analyze the situation rationally. She could be worried about how this will affect Harry and his future, and might try to find a way to reverse the situation if it seems harmful to Harry.
Perhaps there are challenges from their friends and the wizarding community. Some might be shocked or disapproving of their union. This could lead to them having to defend their relationship and face various social pressures. Maybe they have to work together to prove that their marriage can work despite the unorthodox start.
If Harry wakes up with Fleur, it could be a bit of a shock for both of them. But then, they might find that they are drawn to each other's personalities. Fleur's elegance and confidence might attract Harry, and Harry's courage and kindness could win Fleur over. Their relationship could develop as they face challenges together. For example, they might have to fight off some dark wizards who are after a powerful magical artifact. Through these experiences, their bond could strengthen into a deep and loving relationship.
Well, it could be a story where Harry and Fleur are part of a secret mission together. They had to stay the night in a hidden place for safety. When Harry wakes up with Fleur, they might start discussing their next moves in a very friendly and perhaps a bit flirty way. They could exchange stories about their experiences at Hogwarts and Beauxbatons respectively, and then realize they have more in common than they thought.
Obviously, Harry would be the main character, just in a female form. Hermione would also be a very important character. She could be the one to help Harry understand and navigate the new experiences of being a girl in the wizarding world. Ron might also be there, and his reactions to Harry's transformation could add some interesting dynamics to the story.
He could be married to Luna Lovegood. Their relationship in the original series was more of a friendship, but in fanfiction, it could be that they got married. Maybe they were on an adventure together, something went wrong magically, and they woke up married. Luna's unique personality would bring a lot of interesting elements to the story as they figure out their new relationship.
Their friends could have a mix of reactions. Cristina might be initially skeptical, worried that Meredith is making a hasty decision. But as she sees how happy they are, she comes around. Alex could be teasing them a lot, making jokes about their 'unlikely' union. Izzie might be all excited and start planning elaborate wedding parties and showers for them.
Friends from different wizarding groups could react in different ways. The Gryffindors would be celebrating loudly and proudly. The Hufflepuffs might be the ones making sure everyone feels welcome and included in the wedding festivities. Meanwhile, the Ravenclaws could be giving intellectual toasts about the significance of their union in the wizarding world's history.
The Weasleys would be devastated. Bill, Fleur's husband, would feel a mix of gratitude towards Harry and intense guilt for not being able to save Fleur himself. Ginny would be heartbroken, having once had feelings for Harry. Hermione would be in shock and would probably spend a lot of time trying to figure out if there was any way they could have prevented it. Ron would be angry at first, angry at the situation and at the bad guys who put Fleur in danger, but also deeply sad for losing his friend.
At first, his friends might not believe it's Ash. But when he starts to show his usual personality traits, like his determination and kindness, they would start to accept it. They would then start to think about how they can use Ash's new form to their advantage. For example, they could use his ability to fly as Mew to reach places they couldn't before, or his psychic powers to sense danger from afar.
Hermione would probably be a bit skeptical at first. She might worry that Harry is rushing into things. But once she sees how happy they are, she would be supportive. Ron, on the other hand, would be more accepting from the start, especially if there are good feasts at the wedding.