As a Mikaelson twin, Bella would likely become more assertive. In the Twilight series, Bella was often more passive, but in the Mikaelson world, she'd need to be tough. She'd have to learn to use her newfound powers quickly. Also, her relationships would change. Instead of being focused on Edward or Jacob, she'd be dealing with the complex family dynamics of the Mikaelsons. Her sense of loyalty would expand to include her new family, and she might become more calculating in her actions to protect them.
Well, first of all, Bella would develop a stronger sense of self - preservation. In the Twilight world, she was often willing to put herself in danger for others. But as a Mikaelson twin, she'd realize that her life is important for the family's balance. Her fashion sense might change too, as the Mikaelsons are known for their elegant and sometimes dark style. Emotionally, she'd become more guarded. In Twilight, she wore her heart on her sleeve, but with the Mikaelsons, she'd learn that showing too much vulnerability can be a weakness. And her social skills would improve as she has to navigate the political and power - hungry world of the Mikaelson family.
Bella's character would develop a more ruthless side. The Mikaelson family has a long history of doing whatever it takes to protect their own, and as a twin in this family, Bella would be influenced by this. She would no longer be the shy, introverted girl from Forks. She'd become a force to be reckoned with. Her values would shift as she is exposed to the Mikaelson's view of power and loyalty. For example, she might start to see the use of dark magic as a necessary evil in certain situations. Her physical abilities would also change drastically as she trains to be as powerful as her new family members.
If Kol's twin was in Bella's body, her personality would likely change the story a great deal. Kol's twin would probably be more assertive and less passive than Bella. She might not put up with Edward's over - protectiveness in the same way and would be more likely to go off on her own adventures. This could lead to her getting into more dangerous situations or uncovering secrets faster.
When it comes to the other Cullens, like Alice, Kol's sister could be both intrigued and a bit dismissive. Alice's visions might seem like a novelty to her at first, but then she could start to resent them if they interfere with her own plans. And with Jacob, she might be amused by his werewolf nature. She could see him as a more natural predator compared to the 'tame' vampires of the Cullens. Overall, her interactions would be a mix of curiosity, rivalry, and in some cases, friendship.
In this fanfiction, Bella Swan's character could develop in terms of her social skills. Since the Gilberts are often in the center of the town's social scene, Bella would have to adapt. She might start making more friends, not just within the Gilbert family but also among their associates. This would make her more outgoing and less of an outcast. She could also learn how to handle different personalities, which would contribute to her growth as a character.
She might become more protective. As Silas's sister, she would have a natural inclination to safeguard him, which could make her more assertive.
Klaus would probably be very intrigued by Bella. He's used to getting his way with most people, but Bella is not easily swayed. So he might start by trying to charm her, but she would be resistant. For example, he could offer her power or protection, but she would be more concerned about her own values and the people she cares about in Forks.
She might become more assertive. In the Twilight series, Bella is often rather passive, but in the Mikaelson family, she would need to be more forceful to hold her own. She'd have to learn to be more cunning and strategic, like the Mikaelsons are.
Well, perhaps the story could be about Kol's twin as Bella Swan trying to find a way back to her own world. Along the way, she has to navigate the complex relationships in Forks. She might befriend some of the characters like Alice in a different way, sharing with her some of the prophetic knowledge she has from her Mikaelson heritage. And when it comes to the werewolves, she could have a more diplomatic approach compared to Bella, due to her experience dealing with different supernatural factions in her own world.
In an army fanfiction, Bella Swan's character would transform in many ways. Her self - confidence would grow exponentially. She was always a bit self - conscious in the original story, but in the military environment, she'd have to believe in herself to succeed. She'd also become more independent. No longer relying on others to protect her as much, she'd be trained to protect herself and her comrades. And her adaptability would improve, being able to adjust to different military bases, climates, and combat situations.
One possible plot twist could be that Bella, as a Mikaelson twin, discovers a hidden power within herself that is different from the other Mikaelsons. Maybe she has a unique connection to nature, like being able to control certain elements. Another twist could be that she is actually a key to an ancient prophecy that the Mikaelson family has been trying to figure out for centuries. This would put her in a central position in the family's power struggles and relationships. And perhaps she finds out that she was switched at birth and her real family is someone completely different, which would create a whole new set of conflicts and emotional turmoil within the story.
In some fanfictions, Bella's character might become more confident. As an immortal, she no longer has the same fears of mortality. For example, she could be more fearless in facing dangerous situations.