Well, a major theme is often the exploration of duality. Harry has his own set of values and characteristics from the Potterverse, and when combined with Ulquiorra's from the Bleachverse, it creates a duality within him. This can be both physical and mental. Another theme is the idea of outcast. If Harry starts to look and act like Ulquiorra, he may be seen as an outcast in the wizarding world, which was already a bit of an outcast to the Muggle world. And then there's the theme of mystery. The readers are often left wondering how far this transformation will go and what the ultimate outcome will be for Harry.
There are indeed such fanfictions. The idea of combining the two characters in this way can lead to some really fascinating plotlines. For example, Harry could start to exhibit some of Ulquiorra's cold and detached behavior, which would be a huge contrast to his normal self in the original series. This could cause all sorts of chaos and confusion among his friends at Hogwarts. And the way the author might describe Harry's new appearance, similar to Ulquiorra's, could add an extra layer of intrigue to the story.
A fanfiction with godlike Harry Potter and Ulquiorra would likely involve a lot of power dynamics. Harry, with his enhanced abilities, could be seen as a disruptor in Ulquiorra's world. Their interactions might not only be about physical combat but also about ideological differences. For example, Harry's values of friendship and loyalty could clash with Ulquiorra's more detached view of the world. It could also explore how their powers interact, like if Harry's magic can affect Ulquiorra's spiritual form, or vice versa.
A fanfiction with Harry Potter dressing as Ulquiorra could start with Harry being curious about different forms of power and personalities. He discovers Ulquiorra's character from some magical source. As he starts to dress and act like Ulquiorra, he finds that his own magic is affected in strange ways. His Patronus might change in appearance or his spellcasting could become more precise yet colder. He would also face challenges from the wizarding community who don't understand his new guise, but at the same time, he might attract the attention of some dark forces who mistake him for someone with new and dangerous abilities.
Yes, there are probably some out there. You could search on fanfiction websites using keywords like 'Harry Potter looks like Lily' to find them. But it might take some time to sift through all the results.
One common theme is identity. Since she looks like Lily, fem Harry often has to grapple with the expectations and assumptions that come with that appearance. Another theme is relationships. Characters may be drawn to her because of her resemblance to Lily, which can create complex love triangles or strong platonic bonds. For example, Snape might have a different dynamic with her compared to the original Harry.
One common theme is redemption. Ulquiorra, being a rather cold - hearted character initially, may find redemption through his relationship with Orihime. Another theme could be the power of love. Orihime's love, whether it's platonic or romantic in the fanfiction, has the potential to change Ulquiorra.
One more theme is the exploration of Orihime's strength through love. In fanfictions, she might be shown as using her love for Ulquiorra to be braver and more assertive. For example, she could stand up to those who oppose their relationship. Also, the idea of redemption for Ulquiorra through Orihime's love is quite common. He may have done many bad things in the past, but her love gives him a chance to start anew.
One possible plot could be that Harry's appearance causes confusion among the Death Eaters. They might initially mistake her for Bellatrix and this could lead to some comical or tense situations. For example, she could be captured by them thinking she's Bellatrix and then have to use her wits to escape.
One main theme is identity. Harry has to grapple with being the son of Hircine, which is very different from what he thought of himself as before. It's about self - discovery and how this new identity shapes his actions.
One main theme is identity. Harry often has to re - evaluate who he is when he becomes part of a new family. Another theme is acceptance. The new family has to accept Harry, and he has to accept them. For example, in many fanfictions, the new family may have different magical traditions that Harry has to get used to.