You can start by looking on fanfic websites like Archive of Our Own. There are often many well - written Crona x Blair fanfics there. Just search for 'Soul Eater Crona x Blair' in the search bar.
In a Crona x Blair fanfic, the story might center around the power dynamics. Blair, being a powerful cat - witch, could play a role in helping Crona control their own power. For example, she might teach Crona some magic techniques that are different from what they've learned at the DWMA. This could lead to a deeper connection between them as they train together.
One great Crona x Soul fanfiction is 'The Bond Beyond'. It delves into how Crona and Soul's relationship develops in a more in - depth way than in the original series. It shows them learning about each other's pasts and how they grow together. Another one could be 'A Different Kind of Friendship'. This fanfiction focuses on how they start as friends but there are hints of deeper feelings emerging as they face various challenges in the world of Soul Eater.
One possible fanfic could be about Crona's journey of self - discovery. In the world of Soul Eater, Crona has always been an outcast. The fanfic could explore how, as a girl, she tries to break free from the chains of her past and the control of her mother. Maybe she starts to make real friends at the DWMA, like Maka and Soul, and they help her to see her own worth.
One common theme is the exploration of their relationship development. Since they have very different personalities in the original series, fanfics often focus on how they grow closer. Another theme is the support they give each other. Crona, being more reserved and troubled, often receives emotional support from Kid in these fanfics.
One great Soul Eater Kid x Crona fanfiction is 'The Bond Beyond Fear'. It beautifully explores their relationship in a post - series setting. The author does an amazing job of delving into Crona's insecurities and how Kid's presence helps them grow. Another good one is 'A Different Kind of Connection' which shows their relationship from a more comical side at first but then develops into a deep emotional bond. There are also some on Archive of Our Own that are worth checking out if you like this pairing.
A really interesting plot could be Crona's exploration of the world outside of the DWMA. Maybe she goes on a journey on her own for the first time. Along the way, she meets different people and creatures that challenge her view of the world. She could learn about different cultures and ways of life that make her re - evaluate her place in the world of Soul Eater, and this could be a great way to develop her character further.
In a fanfiction about female Crona, her backstory could be delved deeper. For example, we could see how she was treated in her early days in the world of Soul Eater. Perhaps she had some secret talents that were suppressed because of her upbringing. The story could then focus on her journey to discover and embrace these hidden abilities.
Often, the theme of redemption plays a part, especially for Medusa. Also, the theme of loyalty and betrayal can be seen, as Crona's loyalty to Medusa is tested throughout the series. And there's the theme of self - discovery for Crona, with Medusa being a major part of that journey in many fanfictions.