One of the main characters could be a Protoss high templar. This character could be the one who first discovers Harry and decides to take him under his wing. Another could be a Protoss zealot, who is initially skeptical of Harry but later becomes his ally in battles.
In 'Harry Joins Protoss Fanfic', there could be a Protoss dark templar as an important character. This character might have a mysterious past and a complex relationship with the other Protoss. He could be initially at odds with Harry but eventually realizes they have a common goal. Additionally, a Protoss carrier pilot could be another main character. This character could show Harry the might of Protoss technology and how it is used in warfare.
Well, perhaps Harry could discover a magical portal that leads him to the Protoss world. There, he might learn their advanced technology and unique culture. Maybe he uses his magic in combination with Protoss powers to fight off some common enemies.
His family members might also be important characters. His parents, if they are alive in the fanfic, could be the opposite of Harry when it comes to snow. They might be the ones who want to take family pictures in the snow every year, and Harry dreads those moments. Or a younger sibling who is always excited about snow and can't understand Harry's dislike.
Ron could also be a major character. He might have a hard time accepting Harry as a girl at first. But as the story progresses, he could become more understanding and protective of Harry in this new form. And there could be some really funny and awkward moments between them.
Hermione could be one of the main characters. She might be suspicious of Orochimaru's teachings and try to convince Harry that it's wrong. She would be constantly researching about Orochimaru and the type of magic he's teaching Harry to prove her point.
Hermione could be one of the main characters. She might be the one who tries to find Harry and bring him back. She would use her intelligence and knowledge of magic to track him down, all while worrying about his safety.
Rainbow Dash might also be a main character. She's brave and loves adventure. She could take Fem Harry on some wild rides around Equestria and introduce her to the exciting parts of the world. They might even get into some friendly competitions.
A group of misfit soldiers could be main characters too. They are all a bit different and don't quite fit the typical military mold. But together with Harry, they form a unique unit. There might also be a high - ranking officer who takes an interest in Harry's progress and either helps or hinders him depending on the situation.
An older, wiser mentor figure could be included. This person has seen the world and can offer Harry advice on how to grow out of his playboy phase. They could have a backstory of their own, like they were once a playboy or knew someone who was and learned from their mistakes. For example, he could be an old actor who has retired from the limelight and now wants to help the younger generation.
Hermione would surely be involved. She could be Harry's research partner, helping him find relevant medical information in books and scrolls. Her intelligence and thirst for knowledge would be very useful in exploring new areas of medical magic. Another character could be Madam Pomfrey. She could be Harry's mentor, teaching him the basics of wizarding medicine and guiding him in his new role as a medic.
Hermione would surely be there. She might be a fellow professor, teaching a subject like Transfiguration or Ancient Runes. She could be Harry's confidante and help him with academic matters at Hogwarts. Also, Ron could make an appearance, perhaps as a visiting lecturer from time to time, sharing his knowledge of wizarding chess and other aspects of wizard culture.