One possible plotline could be that the Volturi face a new and powerful enemy, perhaps a group of vampires with unusual abilities. The Cullens, with their unique skills and more compassionate nature towards humans, decide to help the Volturi in order to maintain the secrecy of the vampire world. They might use their connections with the human world and their knowledge of co - existing with humans to their advantage in this fight.
One possible plotline could be that Bella tries to hide her admiration for the Volturi from the Cullens. She might secretly collect information about them or have dreams about their world.
I'm not sure of specific 'Cullens help the Volturi' fanfics off the top of my head. But you can try searching on fanfic platforms like Archive of Our Own (AO3). They have a large collection of Twilight - related fanfics and you might be able to find some with that particular plot there.
The Volturi's visit to the Cullens in Twilight fanfiction can bring about various scenarios. It could start with a formal greeting but quickly turn into a tense negotiation. Since the Volturi are known for their strict rules, they might question the Cullens about their relationships with humans, like Bella. They may also be interested in the unique abilities of the Cullens. For example, if there's a new power among the Cullens, the Volturi would want to know more about it. And the Cullens would have to be very careful in how they handle this visit to avoid any conflict that could lead to a battle.
One possible interesting plotline could be Bella's adjustment to her new family life with the Cullens. She has to adapt to their unique lifestyle, which might include things like their dietary habits and their nocturnal activities.
One possible plotline could be about the new generations of avatars exploring uncharted regions of Pandora. They might discover new species and form unique bonds with them.
One possible plotline could be the public's reaction to the divorce. The media frenzy, public opinion polls swinging, and how it affects the political climate. Another could be the division of assets, especially if there are state - related properties or funds involved in some way. And perhaps the role of political parties in either trying to cover it up or use it to their advantage.
A plotline could revolve around Marceline preparing for the arrival of her baby. This might include her building a safe place for the baby, considering how her world as a vampire and adventurer might affect the child's upbringing. It could also show her seeking advice from her friends, like Finn or Jake, who might be both excited and worried about the situation.
Maybe Harry leaves the wizarding world and uses his magical skills in the muggle world as a mercenary. He could be hired for dangerous jobs that require a touch of magic but need to be kept secret from the muggles.
In this fanfic, it could be that Deku's quirk goes out of control during a training exercise. He loses the ability to contain his power and it ends up consuming him, resulting in his death. This would create a lot of self - reflection among the other students about the risks of their quirks and the importance of proper training and control.
One possible plotline could be Naruto having to control the power of the Jubbi. He might struggle at first, but with his determination, he gradually learns to harness it for good, like using it to protect the Hidden Leaf Village from a new, powerful enemy.