There's a fanfiction called 'Twilight's New Bonds' that deals with Paul and Sam imprinting on Bella. It dives deep into the emotional turmoil that Bella experiences when faced with this unique situation. It also explores how the pack dynamics change as a result.
You can try Archive of Our Own (AO3). It has a vast collection of fanfictions, and there are likely to be several stories about Paul and Sam imprinting on Bella there.
A sense of community is sometimes a theme. Their relationship is not just about the two of them. It can affect the werewolf pack and the vampire - human relationships in the 'Twilight' world. So, how they fit into the larger community while being in an imprinted relationship is explored in some fanfictions.
The plot of 'bella is paul's imprint fanfiction' could be really diverse. It might start with Paul realizing he has imprinted on Bella. This could lead to a series of events where they have to navigate their feelings for each other. The fanfiction could also introduce new conflicts, like other werewolves not accepting their relationship or Bella having doubts due to her previous experiences with vampires. It may also include how they overcome these obstacles and build a relationship based on the imprint bond.
One common theme is the struggle with the unexpected nature of imprinting. Paul might be initially resistant to the idea of imprinting on Bella because of her relationship with Edward, for example. Another theme is the power of the imprint bond, which can often override other loyalties and emotions.
There might be a fanfiction where Bella initially resists the imprint. She's used to her own life and the idea of being imprinted on by Sam might be overwhelming. But as the story progresses, she starts to understand the depth of the connection and how it could bring new meaning and protection to her life. The story could explore her internal struggle and the changes in their relationship over time.
Another theme is the reaction of the pack. In a lot of these fanfictions, the pack has to adjust to Sam being imprinted on Bella, which can cause some conflict and interesting dynamics within the group. It's not always easy for them to accept this new situation.
The main characters are clearly Jacob, Sam, and Bella. Jacob is a werewolf who has imprinted on Bella. He is often portrayed as passionate and protective. Sam is also a werewolf and his imprinting on Bella creates a lot of the story's conflict. Bella, of course, is the human at the center of this supernatural love triangle. She is known for her strong will and her connection to the vampire world as well, which adds more complexity to the story.
There are numerous Bella Sam imprint fanfictions out there. A great one is 'The New Path' which shows how their relationship evolves over time. It starts with the confusion of the imprint and then progresses into a deep, loving connection. Some fanfictions focus on the reactions of the pack to Sam's imprint on Bella, like 'Pack Reactions to Sam and Bella' which adds an interesting layer to the story.
There's also 'Paul's Imprint on Bella: A New Chapter'. This story focuses on the immediate aftermath of Paul imprinting on Bella. It shows how the other characters in the Twilight world react to this unexpected turn of events, adding a lot of drama and new plot twists.