To write a Summer RWBY FBI fanfiction, start by establishing the rules of your crossover. Decide how the FBI exists in the RWBY universe. Is it a secret organization that has been hidden? Then, think about Summer's role. Maybe she's a double agent. Next, plan out the plot. It could involve a mystery that only Summer, with her knowledge of both worlds, can solve.
One interesting Summer RWBY FBI fanfiction could be about Summer Rose having a secret connection to the FBI in a Remnant - like world. Maybe she's working undercover to uncover a conspiracy that threatens Vale. However, it's a rather unique crossover idea, so there might not be a ton of such fanfictions out there. You could start by looking on major fanfiction platforms like Archive of Our Own.
One common theme is mystery. Since Summer Rose has a lot of mystery surrounding her in the RWBY series, adding the FBI - like elements often means there's an investigation into her past or her disappearance. Another theme could be the clash of two different worlds, the RWBY world of Huntsmen and Grimm and the more modern - day, law - enforcement - like FBI world.
There are some interesting RWBY Summer Rose fanfics related to FBI concepts. One can start by looking on fanfic platforms like Archive of Our Own. You might find stories where the FBI - like elements add an interesting twist to the RWBY universe, perhaps with Summer Rose involved in some sort of mystery or adventure that has elements of FBI - style investigations.
Yes, in some RWBY fanfictions, Ruby can be depicted as the Summer Maiden. Fanfiction allows for creative interpretations and alternate storylines, so it's not uncommon to see such a concept explored.
The plot could center around Summer's return and how it affects the current state of affairs in the RWBY world. Maybe she comes back with new powers or knowledge that she imparts to the other characters. It might also deal with the emotional impact of her return on her family and friends, especially Ruby who has grown up without her mother for a long time. There could be battles and challenges that Summer has to face as she reintegrates into this world, and she might be a key factor in solving some greater threat that the RWBY characters are facing.
Most fans would be shocked. Since Taiyang is seen as a family - man in the RWBY world, this would be a huge deviation from his character. Some might be intrigued as it adds a new layer of drama, but many would also be disappointed as it goes against the positive image of the character.
I don't think it's that common. Taiyang is usually depicted as a loyal person in RWBY lore. Fanfiction can be a wild place though. But most RWBY fans like to keep the characters' core values intact. So while there may be some out - there fanfictions with this idea, it's not something you'll see everywhere. It might also be a way for some writers to explore the darker side of the RWBY world, but it's not in line with the overall positive image of Taiyang.
One great fanfiction could be 'Summer's Legacy'. It delves into the relationship between Taiyang and Summer. It shows how their bond was not just romantic but also how they influenced each other in their Huntsman and Huntress careers. Another interesting one might be 'Taiyang's Memories'. This one focuses on Taiyang's perspective after Summer's disappearance, his memories of their time together and how he copes with raising Ruby and Yang alone. There are also some that explore their adventures as a team before Ruby was born.
Well, a lot of the fanfiction about Taiyang and Summer focuses on their past. Their time as students or young Huntsmen and Huntresses. This often includes themes like friendship, as they had friends in their teams. And loyalty, to their friends and to each other. Another common theme is the mystery surrounding Summer's disappearance. Fanfictions try to fill in the blanks and come up with different theories about what might have happened to her.