The theme of self - discovery is also common. Ash, through his relationship with the female legendary Pokemon, discovers new aspects of himself. He might learn about his hidden strengths or his true purpose in the Pokemon world. Meanwhile, the female legendary Pokemon may also discover her own emotions and the importance of co - existing with humans. This theme adds depth to the characters and makes the fanfictions more interesting.
Another theme is the power of friendship. The female legendary Pokemon often starts off as a powerful and somewhat aloof being. But through her interactions with Ash, she learns about the value of friendship. They then go on to face powerful enemies together, relying on their friendship to overcome difficulties. This theme is well - loved as it shows how even the most powerful Pokemon can benefit from human friendship.
Arceus is quite popular. Given that it's considered the creator of the Pokemon universe in the official lore, it often has a significant role in fanfictions. Mewtwo is also very common. Its powerful psychic abilities and complex backstory make it a favorite for fanfic writers to explore. Another popular one is Lugia. With its majestic appearance and its connection to the sea, it's often a central figure in many stories.
One reason is that it gives more depth to Ash's character. When he's paired with a Legendary, we get to see how he adapts, grows, and learns from such a powerful partner. For example, in some fanfics where he's with Arceus, he has to deal with the responsibility of being associated with the 'God' of the Pokemon world. It also adds an element of the extraordinary to the Pokemon universe we already know and love.
I'm not sure as I don't typically read such fanfictions. But I would assume some common themes could be the exploration of a unique relationship between Ash and the legendary pokemon, perhaps some kind of power dynamic due to the legendary pokemon's abilities.
One great Ash x Female Legendary Pokemon fanfiction is 'The Legendary Bond'. It beautifully weaves a story of Ash's encounter with a female Suicune. The story focuses on how they gradually form a deep connection through their adventures together, facing various challenges in the Pokemon world.
Protection is also a big theme. Often, Ash has to protect the female legendary Pokemon from villains who want to capture or harm it. This shows Ash's heroic side and also the vulnerability of the legendary Pokemon. In some stories, the female legendary Pokemon also protects Ash in return, highlighting the mutual care between them.
Mewtwo is also very popular. Given its origin as a genetically - engineered Pokemon, a human could interact with it in many ways. Maybe a human scientist wants to study Mewtwo further, or a young trainer tries to befriend Mewtwo and help it come to terms with its existence and powers.
One of the popular pairings is Ash and Pikachu with a Legendary Pokemon like Mewtwo. They could form an unlikely alliance to fight against a common enemy. Another could be Ash and a female trainer along with a Legendary Pokemon, like Ash, Misty and Lugia. Their combined skills and the power of the Legendary Pokemon make for an interesting dynamic.
One popular plot twist could be that Ash discovers he has a special power given to him by the Legendary Pokemon that raised him. For example, he might be able to communicate with all Pokemon telepathically. Another could be that the Legendary Pokemon that raised him is in danger, and Ash has to use his unique bond with it to save it from an evil organization. And sometimes, there's a twist where Ash's real family is somehow connected to the Legendary Pokemon world, and his upbringing by the Legendary Pokemon was part of a bigger plan to reunite his family.
In such fanfictions, a common theme is the exploration of love and attraction in a different context. With Ash crossdressing, it can add a new layer to the relationship between him and Dawn. It might make Dawn see Ash in a new light, or it could be a source of confusion for her feelings. Another theme could be the impact on their Pokémon. How do the Pokémon react to Ash's new appearance? Do they treat him any differently? This can also create interesting storylines.
One popular theme is Ash's unique hybrid abilities and how they affect his journey. For example, if he was part Pikachu, his speed and electricity - related skills could give him an edge in battles. Another theme is his relationships with other hybrids. It could lead to interesting team dynamics, like having a hybrid Charizard as a partner and how they communicate differently. Also, the struggle of being a hybrid in a world that may not fully accept such beings is often explored, adding depth to the story.