Well - developed characters are key. If the fanfic delves deep into sakura's character, showing her growth, fears, and dreams, it will be more engaging. Also, adding complex relationships with other characters, not just the usual ones, can make it stand out. It could be her friendship with an outcast character or a rivalry that turns into an unexpected alliance.
Toge Inumaki is important too. His special cursed speech ability makes him stand out. Also, the principal of the school, Masamichi Yaga, is likely to be important as he is in a position of authority and has an influence on Gojo and the other students. There could be other characters like the members of different clans that also play roles in the complex web of the story.
Sakura can stand out by showing her medical ninjutsu skills. Since she has a natural aptitude for it, she could use it in creative ways during the exams. For example, she could heal her opponents during a fight to show mercy and strategic thinking, which is not a common approach in the Chunin Exams.
A unique plot. For instance, if it takes the story of Sakura in a completely unexpected direction, like making her a time - traveler in a Sakura - centric story. This kind of out - of - the - box thinking can make a fanfic stand out.