She might be more secretive. Knowing that her father had a dark past due to the Sharingan's influence, she could be more guarded about her own past and family. For example, she might not be as open with her friends in Konoha as she was originally.
Yes, in some fanfictions, creative interpretations might make Sakura Haruno be related to Yagura as his daughter. Fanfiction allows for a lot of such unique and often unexpected relationships to be explored.
One possible storyline could be that Sakura has to deal with the expectations and secrets related to her father's past. For example, if Yagura had some dark deeds in his past, Sakura might struggle to come to terms with it.
She might become more ruthless. Jashin's ideology often involves sacrifice and extreme measures. So Sakura could lose some of her compassion that she was known for. For example, she might be more willing to harm others in the name of Jashin.
One possible plot could be that Sakura, as Yagura's daughter, discovers her true heritage later in life. She might struggle with the implications of being related to someone who had a complex history in the ninja world. For example, Yagura was once under the control of the Sharingan. Sakura could face prejudice from those who knew of her father's past. But she could also use her own skills and the knowledge of her family connection to try and redeem her father's name in the eyes of the ninja community.
Sakura's personality could become more competitive. In the ninja world, male characters are often shown to be more competitive. So, as a boy, she might be eager to prove herself against other male ninjas. She could also develop a more laid - back attitude in some aspects, like not being as self - conscious about her appearance as she was when she was a girl.
She might become more confident, or overconfident. Having the Death Note gives her a huge advantage over her enemies. She could start to rely too much on this power and think she can solve all problems with it. This could lead to her making mistakes and alienating her friends.
She might become more aggressive. Saiyans are known for their fighting spirit and aggression in battle. Since Sakura is a fan, she could start to adopt some of these traits. For example, she may be more willing to take on opponents head - on rather than relying on her more strategic ninja approach all the time.
Her relationship with Sasuke might become more complex. Sasuke, having his own experiences with dark powers, could be either more drawn to her or more worried about her. Naruto, on the other hand, would probably be very concerned and try to support her through it.
There might be some out there. You could try searching on fanfiction platforms like FanFiction.net or Archive of Our Own. Just type in 'Sakura Haruno Yagura's sister' in the search bar and see what comes up.
Her confidence would likely grow even more. Sakura already has a strong sense of self - confidence in Naruto, but as Catwoman, she would be in a new and different world where she has to rely on herself even more. She might also develop a bit of a mischievous side, which is characteristic of Catwoman. This would be a new aspect to her personality, as she is usually more serious in Naruto.