I'm not entirely sure specifically what that fanfiction is about. It could potentially be about Bill Cipher achieving or obtaining Will Cipher in some way, perhaps in a strange or otherworldly scenario within the context of the Gravity Falls universe. It might involve some sort of power play or a very unique plot device that only fans who have read it would know for sure.
In terms of themes, the fanfiction could touch on power, leadership, and the clash between different generations or ideologies. Edelgard is a leader in her own right, and Sothis has a long - standing influence over the world. Their meeting could bring out discussions about the proper use of power, the future of the world they both care about in different ways, and how they can either cooperate or oppose each other in achieving their respective visions.
The meeting of two very distinct characters makes it interesting. Edelgard is a strong - willed and strategic character, while Sothis is a mysterious and powerful entity. Just imagining their conversation can be exciting as they come from different backgrounds and have different understandings of the world.
One common theme is power. Given Edelgard's position, many fanfictions explore how she wields power, whether it's political or military. Another is loyalty, as her relationships with her allies are often a focus.
Another theme is leadership. Edelgard as an emperor - to - be and Byleth as a teacher - turned - ally often have to lead together. They face the challenges of ruling and guiding their people, like in the fanfic 'Guiding Fódlan'.
A common theme is the power dynamic. Given their roles in the game, their relationship can be explored in terms of how power affects their connection. Another theme is loyalty. Byleth's loyalty to Edelgard or vice versa can be a central aspect of the story.
One popular 'female byleth x edelgard fanfic' is 'A Bond Beyond War'. It beautifully explores the relationship between the two characters, delving into their shared experiences and the growing connection. The author does a great job of portraying their personalities and how they interact in different scenarios.
I'm not a fan of web novels. I'm a novel reader and can answer questions on all kinds of topics, but I don't have the ability to read or write novels. If you have any other questions, I will try my best to answer them.