Well, as humans, Elena could be less of the damsel in distress. She could be more assertive and have her own set of goals that don't revolve around vampires or the supernatural. For Klaus, he could lose his violent tendencies and instead be a more brooding artist type. He might use his creativity to deal with his past traumas.
In a human version, Elena could be a fearless journalist always on the hunt for a big story. Klaus could be a mysterious and wealthy entrepreneur who is trying to hide some dark secrets from his past. As they cross paths, Elena starts to dig into Klaus's secrets. Their relationship develops as Klaus tries to keep her at bay while also being drawn to her tenacity. This is very different from their original vampire - related characters.
If we make them human, Elena could be a very social and outgoing girl who loves adventure. She could be into extreme sports and traveling. Klaus, on the other hand, could be a shy and introverted writer. They meet in a writing workshop where Elena encourages Klaus to come out of his shell. Their relationship grows as Klaus writes about their experiences together, and they both change in the process. Their development is not related to the vampire - werewolf drama of the original.
Ben could be more outspoken in fanfiction. In the show, he's often a bit reserved as a ghost. But in fanfiction, he could be the one pushing Klaus to face his demons more directly. This would show a different side of Ben, perhaps one that was hidden in the show because of his limited means of communication as a ghost. It also changes the nature of their relationship, making it more of an equal partnership in growth.
In fanfiction, their characters can be developed more freely. For example, Hal might be shown as more vulnerable than in the original show. Maybe he has a harder time controlling his vampire instincts and Alex has to help him. This is different from the show where he usually has a better grip on himself.
In this fanfiction, Elena could start off as a more adventurous character. When she meets Damon, she's not as focused on the normal things in her life like school and friends. Instead, she's eager to explore the unknown with Damon, which would lead to a different kind of relationship. She could be the one dragging Damon into new situations rather than the other way around, and this would shape her character in a unique way.
For fem Kuroko, her character could be developed with more emphasis on her femininity. She might use her charm or intuition in ways that male Kuroko didn't. For example, she could be more in tune with the emotions of her teammates and use that to boost team morale. Aomine, on the other hand, as a female could be developed with a different kind of competitiveness. Instead of just brute strength, she might use her intelligence and strategic thinking more, like finding ways to outwit opponents through psychological warfare.
In fanfiction, Roxas might be developed to have more complex emotions about his existence. For example, he could struggle more with his identity as a Nobody and his connection to Sora in ways not fully explored in the game. Xion, on the other hand, could be given more backstory about her creation. Maybe the fanfiction delves deeper into the experiments that led to her existence.
Well, in fanfiction, you could develop Sgt Frog's human form character by emphasizing his confusion in the human world more. For instance, he could constantly misinterpret human social cues, leading to humorous situations. Maybe he thinks a simple handshake is a sign of a lifelong bond and gets really attached to people after just one handshake.
Naruto could be given a more complex personality in the modern fanfiction. He might be more introverted at first, having to deal with the loss of his father in a modern way (like through memories in a digital photo album). Kushina, on the other hand, could be shown as having a secret past that is slowly revealed through modern - day detective work by Naruto and his friends, which would be a big departure from her straightforward backstory in the original.
Dark Naruto could be developed to have a different set of ninja skills. He might learn some forbidden jutsu on his own in his journey to the dark side, which gives him an edge over others. In terms of Fem Sasuke, she could be more in tune with her feminine side. Instead of just being cold and brooding like the original Sasuke, she could use her charm and intelligence to get what she wants. For instance, when dealing with enemies, she might use her wits to outsmart them rather than always relying on brute force. Also, Dark Naruto could have a more philosophical side, constantly questioning the nature of power and the ninja world, which is different from the more impulsive original Naruto.
Well, in fanfiction, their relationship might bring out different aspects of their personalities. Since they are married, Tony could be more protective and less of the joker he was in the original show. Ziva, on the other hand, might be more open about her emotions, especially when it comes to her relationship with Tony. This is different from the original show where she often kept her feelings bottled up. The married state in fanfiction gives them a new environment to grow and change as characters.
One way their characters are developed differently in fanfiction is through their parenting styles. In the original series, since they die early, we don't really see them as parents. But in fanfiction, we can see different approaches. Minato could be the strict yet loving father, teaching Naruto advanced ninjutsu from a young age. Kushina could be the nurturing mother, always making sure Naruto is emotionally okay. Additionally, their characters can be developed in relation to the political situation of the village. They could be involved in secret political maneuvers to protect the village and Naruto's future as a potential great ninja.