Romance is also likely to be a prevalent theme. Writers might explore the relationship between Ichigo and Female Ukitake, how they first meet, and how their feelings develop over time. This could involve elements of forbidden love, as they may come from different backgrounds or have different responsibilities within the Bleach world.
You can try some popular fanfiction websites like Fanfiction.net or Archive of Our Own. These platforms usually have a wide range of fanfictions, and you might be able to find some related to Ichigo and Female Ukitake there. Just use the search function and type in relevant keywords.
A common theme is the exploration of their dual natures. Since Ichigo has his own powers and the female hollow ichigo has her unique hollow characteristics, fanfictions often play with how these two different yet connected aspects interact.
A common theme is the healing aspect. Given Ukitake's health issues, the OC often plays a role in either physically or emotionally healing him. Another theme is discovery, as the OC discovers the secrets of Soul Society with Ukitake as their guide.
A common theme is the exploration of their relationship. Since they are both from the Bleach universe, many fanfictions will focus on how their different personalities interact. For example, Ichigo is often headstrong and Toshiro is more reserved, so seeing how they overcome these differences can be interesting.
One common theme is the idea of two very different personalities coming together. Ichigo is often impulsive and hot - headed, while Byakuya (even as a female) is more reserved and composed. Their interactions based on these differences can lead to interesting character dynamics.
The theme of trust also frequently appears. Given the nature of Aizen's character in the original series, a female Aizen in fanfiction would likely have an issue with others trusting her. Ichigo, with his trusting nature, has to decide whether or not to put his faith in her. This creates a lot of tension and drama in the fanfictions.
Love and attraction is also a very common theme. Given their different personalities, it's interesting to see how they might fall for each other. Some fanfictions focus on the slow - burn aspect of their relationship, with small moments of flirtation and growing affection that build up over time.
One common theme is the exploration of gender differences. Since Ichigo is female in these fanfictions, it often looks at how she is treated differently in the male - dominated Soul Society. Another theme is relationships. It could be her relationships with her friends like Chad and Orihime, but also her romantic relationships which might be different from the original story.
One common theme is the exploration of their relationship. Since they are from different sides in the original story, seeing how they interact and form a connection in fanfiction is fascinating.
One common theme is identity. Since Ichigo is now female in these fanfictions, she often has to re - define herself in the new crossover worlds. Another theme is power. How her spiritual powers from the Bleach world interact with the powers in the other crossover universes, like magic in a fantasy world or special abilities in a sci - fi setting.