Well, it could be a swan. A swan is often associated with beauty and elegance. If Harry was a girl, she might possess these qualities in a more pronounced way. The swan Patronus would also show her inner strength, as swans are known to be protective of their territory and young, much like Harry would be in the fight against the Dark Arts.
If Harry was a girl in fanfiction, her Patronus could be a doe. Since a doe was Snape's Patronus, and if female Harry had a connection with Snape (even if a different kind), it could be a doe. It would represent her kindness and grace.
Her Patronus might be a fox. Female Harry could be seen as cunning and quick - witted like a fox. It would also symbolize her ability to adapt to different situations at Hogwarts, whether it's dealing with school rivalries or the threat of Voldemort.
She could be Harriet Potter. It's a simple and obvious choice that still keeps the connection to the original name while clearly indicating the gender change.
One interesting Harry Patronus fanfiction could be where Harry discovers a new form of Patronus magic that has been long forgotten. This could lead to him having to face new dark forces with this enhanced power.
One common theme is the power of hope. Harry's Patronus often represents hope in the face of darkness, like in the original series. Fanfictions usually expand on this, showing how his Patronus can inspire others as well.
A unicorn Patronus is another special one. Unicorns are known for their purity and magic. In fanfiction, a character with a unicorn Patronus might be pure of heart and have a deep connection to the more innocent and natural aspects of magic. They could be more in tune with the forest and the magical creatures that live there, and perhaps have the ability to heal or soothe others with their magic.
In this fanfiction scenario, her personality could be quite different. She might be more nurturing than the male Inuyasha. For example, when it comes to taking care of Shippo, she could be more motherly. However, she would still have that fierce and independent streak. She would likely be more vocal about her feelings, especially when it comes to matters of the heart. And while she would be tough in battles, she might also show more mercy to her opponents because of her female nature. This new personality would bring a fresh perspective to the story and the interactions with other characters.
Well, such a fanfiction would likely rewrite a lot of the original plot. Harry as a girl might face different challenges at Hogwarts. There could be more focus on her dealing with the typical girl - related issues in a magical world, like how she dresses for the Yule Ball in a different way than the original Harry. Her relationship with Draco could also be different. Instead of just being rivals, there could be a more complex, perhaps romantic, undertone to their interactions as she, as a girl, might be seen as more of a threat or an object of interest to Draco in a different sense.
I've read a fanfic where the main character has a fox patronus and they use it to explore the Forbidden Forest. It was really exciting as they discovered new magical creatures with the help of their patronus's senses.
In some Harry Potter fanfictions with a fox patronus, the author might explore the symbolism of the fox. The fox is often seen as clever and sly in muggle folklore, so perhaps in the fanfic, the character with the fox patronus uses these traits to outwit dark wizards or solve mysteries within Hogwarts. For example, they could use their fox - like cleverness to figure out the secrets of the Chamber of Secrets in a new and different way than what was shown in the original books.
A pegasus Patronus is also a great concept in fanfiction. Pegasus represents grace and freedom. A character with a pegasus Patronus might be someone who values these qualities. They could be the type of person who is always looking for a way to break free from constraints, whether it's social norms or dark magic threats in the wizarding world. This Patronus could also suggest a connection to the skies and a more spiritual side of magic.
One common theme is identity. Since having a snake patronus is often associated with Slytherin and dark magic in the original series, characters in the fanfiction often struggle with how this patronus defines them. Are they really different from the 'good' Gryffindors? Another theme is secrecy. A snake patronus can be seen as something to hide, so there's often a plot around keeping it a secret or the consequences of it being revealed.