One common theme might be the exploration of a unique relationship dynamic. Since Bella is feral, it could involve Jasper having to deal with her wilder nature in contrast to his more controlled self.
I'm not sure of a specific 'bella is feral jaspers mate fanfic' off the top of my head. You could try searching on popular fanfic websites like Archive of Our Own. They have a vast collection of fanfictions and you might be able to find what you're looking for there.
A key element is the relationship development between Bella and Jasper. It should show how they come to be mates, perhaps starting from an initial attraction or a shared experience within the Twilight - like setting.
Yes, there are several. You can try searching on popular fanfic platforms like Archive of Our Own. Just type in the relevant keywords, and you'll likely find some interesting stories. However, the quality can vary, so it might take some time to find one that really suits your taste.
There could also be an external threat that forces them to put aside their differences. For example, a new vampire or a group of enemies might attack their community. In this situation, Edward, Bella, and Jasper have to work together. During this time, Edward might realize that his jealousy is unfounded, and they all form a stronger bond as a result.
Well, he might try to distance himself from Bella at first. Maybe he'll avoid being around her and Jasper together, thinking it'll help him get over his jealousy.
One great 'bella is jaspers mate' fanfic can be found on Fanfiction.net. It has a really interesting plot where Bella and Jasper's relationship develops in a unique way against the backdrop of the Twilight universe.
The idea of Bella being Carlisle's mate in a feral state is interesting because it's a departure from the normal relationship dynamics in the original story. It adds an element of the wild and unpredictable to their connection.
A frequent theme would likely be the intensification of their romantic relationship. By Bella taking the lead in seducing Edward, it can lead to more passionate and perhaps more complex emotional interactions between them. Also, it might explore themes of power dynamics within their relationship, as Bella is usually the more vulnerable one in the original, but here she's in a more dominant position in terms of the seduction.
One common theme is the exploration of a unique relationship. Since Bella and Tanya are not the most obvious pairing in the original lore, fanfictions often focus on how they come to terms with being mates. Another theme is the struggle against society's expectations. Vampires in these stories might have certain views on who should be with whom, and Bella and Tanya have to fight against that.
In 'bella and paul mate fanfiction', the theme of transformation is often present. Not just Bella's potential transformation into a werewolf's mate, but also the transformation of their relationship from hostility or indifference to love. There is also the theme of protection. Paul is a werewolf and has a natural instinct to protect, and this plays a big role in how he relates to Bella. And of course, the theme of love against all odds, as their relationship is not an easy one considering the complex world of Twilight that they are a part of.