Yes, there are quite a few. You can find them on popular fanfiction websites like Archive of Our Own. Some of them explore unique relationships between a female Luffy and Zoro, often with interesting plot twists and character developments.
One common theme is adventure. Since they are pirates, stories often revolve around them going on quests and facing challenges together. Another theme is loyalty. Zoro's loyalty to Luffy is a big part of their relationship in the original series, and this is carried over and sometimes even deepened in fanfictions.
A fanfiction named 'Zoro and Luffy's Unusual Alliance' is quite good. It starts with a situation where the crew is in a big trouble. Female Luffy's leadership and Zoro's unwavering loyalty create an interesting dynamic. The story is full of action and also some really heart - warming moments between the two characters as they rely on each other to get through difficulties.
One common theme is loyalty. Just like in the original series, their loyalty to each other is often emphasized. Another theme could be growth, both as individuals and in their relationship.
I would recommend 'Three Souls, One Dream'. It has an interesting take on their interactions, showing how Zoro, Luffy, and Sanji grow together as a team. It has some really heartwarming moments that capture the essence of their friendship.
The chemistry between them. Luffy's carefree and determined nature, Zoro's cool and strong - willed self, and Sanji's passionate and sometimes flirty character create a really interesting mix. When they interact in a fanfic, it can lead to some really fun and engaging moments.
Another theme is rivalry. Zoro and Sanji have a friendly rivalry which can be elaborated on in fanfictions. For instance, they might compete in a friendly tournament on the ship to see who is stronger or more useful in a certain situation.
In these fanfictions, their relationship can develop through shared battles. When they fight side by side against tough opponents, they understand each other better and their trust deepens.
Character growth is also important. As they go through different situations in the fanfic, they should learn and develop. In 'The Changing Tides' fanfic, Zoro learns to be more open about his feelings towards Luffy, and Luffy becomes more aware of Zoro's sacrifices, which makes the relationship between them more profound and complex.
One common theme is friendship. Since Luffy and Zoro are crewmates in the original, in fanfiction with a female Luffy, their friendship still remains central. Another theme is loyalty. Zoro's loyalty to Luffy is often emphasized in a different light when Luffy is female. Adventure is also a big theme, as they go on various quests together just like in the original series.