Yes, there are quite a few. You can check out some popular fanfiction websites like Archive of Our Own. Just search for the tags 'fem Harry Potter' and 'Fate Stay Night' there, and you'll find various stories that combine elements from both universes in interesting ways.
The settings are different. Harry Potter is set in a wizarding world with places like Hogwarts, Diagon Alley, and the Forbidden Forest. Fate Stay Night is set in a modern - day Japanese city with a hidden world of the Holy Grail War. Also, the characters are distinct. Harry Potter has characters like Harry, a young wizard, and Dumbledore, a wise old wizard. Fate Stay Night has characters like Shirou, a normal high - school student turned Master, and Saber, a powerful Servant.
No. Harry Potter is a completely separate and original fictional universe created by J.K. Rowling, while Fate Stay Night is another distinct work. They have their own unique storylines, characters, and settings, and there is no such relation of Harry Potter being a fanfiction of Archer Fate Stay Night.
The combination of two very different universes makes it unique. Harry Potter's world is about witches and wizards in a school setting with a fight against dark magic. Fate Stay Night has the Holy Grail War concept. A fem Harry Potter in this crossover can bring new dynamics, like different relationships and ways of using magic.
One common theme is the exploration of different magical systems. Since both Harry Potter and Fate Stay Night have their own complex magic, fanfictions often explore how these magics interact or compare. For example, how the spells in Harry Potter would fare against the magecraft in Fate Stay Night.
One common theme is identity. Since Harry is now female in these fanfics, there's often exploration of how she adjusts to this new identity within the Fate Stay Night world. Another theme is power. How her existing powers from the Harry Potter universe might translate or be different in the Fate Stay Night setting.
She would face a lot of challenges. Firstly, cultural differences. The Fate Stay world has its own cultural and mythological backgrounds that are different from the Harry Potter universe. She would need to understand and respect these differences to function well. Secondly, power - wise, there are many powerful Servants in Fate Stay. She would have to find a way to compete and hold her own. This might mean she has to constantly train and improve her skills. Also, in terms of her identity, she has to balance being Harry Potter with being a Caster in Fate Stay. If she leans too much towards her Harry Potter side, she might not fit in, but if she abandons it too much, she loses what makes her character interesting.
Well, the most obvious change would be in the character dynamics. A female Harry Potter as a Caster in Fate Stay would bring a different energy. Since Harry is known for his courage and quick - thinking, as a female, those traits could be expressed in a more nuanced way. For example, she might use her femininity to her advantage in certain situations, like in negotiations or when dealing with male characters. Also, her magic, which is already quite powerful in the Harry Potter universe, could be adapted in interesting ways in the Fate Stay setting. Maybe her spells would have a different aesthetic or a new level of power.
If Harry Potter were to watch Fate Stay Night fanfiction, he might start thinking about how different the rules of magic are. In his world, magic is more about spells and potions, while in Fate Stay Night there's a whole other level of magic with summoning Servants and the power struggles for the Grail. He could also get some new ideas about heroism and sacrifice from the characters in the fanfiction.