Well, in Adrien Agreste depressed fanfiction, it often delves deep into his complex character. His depression could be due to his strict family life, especially his over - controlling father. Fanfiction writers might explore how he copes with his dual identity as a model and a superhero. They may show his isolation and how he tries to hide his true feelings from his friends.
The theme of unrequited love can also be present. He might feel that Ladybug will never truly love him for who he is, especially when he is in a depressed state. This adds another layer of sadness to his character and the story.
One great fanfiction is 'The Secrets of Gabriel Agreste'. It delves deep into his motives and the backstory that we don't often see in the show. It gives a more complex view of his character.
In many fanfics, female Adrien is portrayed as having a strong sense of justice, just like the male version. However, she may show it in a more empathetic way. For instance, when dealing with akuma - victims, she might be more in tune with their emotions and try to help them on a deeper emotional level. Also, her relationships with other characters, especially with Chloe, can be more complex. Since they are both girls, there could be more of a cat - fight - like dynamic in some stories.
Well, a fanfic about them falling in love might also focus on the internal struggles they face. Gabriel is so focused on his goals related to the Miraculous that he might initially resist his feelings for Nathalie. Nathalie, on the other hand, might be hesitant because of her position as his assistant and the power imbalance. But as the story progresses, these barriers could be broken down, leading to a beautiful and perhaps bittersweet love story.
It could be Lila Rossi. Since she's a master manipulator, she could find out about Gabriel's identity as Hawkmoth. Maybe she tries to blackmail him into doing something for her, but Gabriel refuses. In retaliation, she somehow manages to get an akuma and send it to Gabriel, causing his akumatization. Lila might think that by akumatizing Gabriel, she can gain more power and control in Paris.
The fanfiction should also fit well within the world of Miraculous Ladybug. It should respect the existing lore and character relationships. If it can add new elements to the story while still feeling like it belongs in the same universe, that's a great sign of a good Gabriel Agreste fanfiction.
Love and acceptance are also very common themes. The relationship between Felix and the reader is usually about them learning to love and accept each other, flaws and all. There's often a theme of mystery as well, since Felix is a rather mysterious character in the original. Fanfiction writers like to explore this mystery further in relation to the relationship with the reader. Additionally, growth - both personal and in the relationship - is a typical theme. As the story progresses, both Felix and the reader change and develop.
One interesting plot could be the sister helping Adrien deal with his double life as a model and a superhero. For example, she might accidentally discover his secret identity and then work behind the scenes to keep it safe from Hawk Moth.
Well, perhaps Gabriel discovers that Adrien has been secretly helping Ladybug and Chat Noir. This betrayal, in his eyes, could lead to his akumatization. As an akumatized villain, he might have the ability to create dark illusions of everyone's worst fears. He uses these illusions to try and break the will of the superheroes and force them to reveal their identities. He could also use his power to turn the citizens of Paris against Ladybug and Chat Noir, making it even more difficult for them to operate.