Maybe Sakura and Hermione could become friends. They both are intelligent and strong - willed. Sakura could show Hermione some of her combat skills, while Hermione could introduce Sakura to the vast magical library at Hogwarts. They could team up to solve some mysteries that involve both the ninja world and the wizarding world, like a dark wizard trying to steal ninja secrets for some evil plan.
Another possibility is that Sakura gets lost in a magical portal and ends up in the wizarding world. She then discovers she has some latent magical abilities because of her chakra. Harry Potter and his friends take her under their wing. Sakura starts to learn magic, and in return, she teaches them some ninja stealth and combat moves which come in handy during their battles against Voldemort's followers.
One idea could be that Sakura, with her medical ninja skills, ends up at Hogwarts as an exchange student. She might use her chakra control to enhance the potions class, for example, by being able to precisely measure and mix ingredients in a unique way. Another plot could involve Sakura getting involved in the fight against Voldemort. Her combat skills and ability to sense danger could be very useful in the wizarding world.
One idea could be a crossover with the Harry Potter universe. Sakura could be a transfer student to Hogwarts, bringing her ninja skills and knowledge of chakra into the wizarding world. Maybe she'd be sorted into Gryffindor for her courage. Another idea is a crossover with the Avatar: The Last Airbender world. Sakura could learn bending techniques and use her medical skills to help in the fight against the Fire Nation. She might also form an interesting bond with Katara, sharing their knowledge of healing.
One idea could be that Sakura, with her medical ninjutsu skills, ends up in the Feudal era of Inuyasha. She could help treat the wounds of the villagers who are often attacked by demons. Inuyasha might be initially suspicious of her strange powers but gradually come to respect her as she proves her worth in battles and in healing the injured. For example, when Inuyasha gets seriously injured in a fight against a powerful demon, Sakura's medical skills could be the key to saving him, which would change his view of her.
One plot idea could be that Sakura, with her medical ninjutsu skills, ends up in the Inuyasha world and helps to heal some of the injured villagers. Her knowledge of herbs and healing techniques could be a new concept in that world. Another idea is that she gets involved in the search for the Shikon Jewel. Since she has combat skills from her ninja training, she could assist Inuyasha and his group in fighting off demons who also want the jewel. Maybe she could even form a friendship with Kagome, and they could learn from each other's strengths.
She might also be a Ravenclaw. Sakura is very intelligent and a quick learner. In the Naruto world, she studied hard to become a skilled medical ninja. At Hogwarts, she would thrive in an environment that values knowledge and wisdom, using her intelligence to solve problems and come up with new magical theories or techniques.
One possible storyline could be Sakura using her medical ninjutsu skills to heal the Avengers after a big battle. For example, she could help Captain America with his old - age related injuries. Another could be her teaming up with Black Widow in a stealth mission. Since Sakura has combat skills from Naruto's world, she could bring a new perspective to the Avengers' operations.
A possible plot is that Sakura is mistaken for a powerful Soul Reaper in the Bleach universe. As she tries to figure out how to get back to her own world, she gets involved in the fight against Aizen. Her strength and determination from the Naruto world help her hold her own against the powerful enemies in Bleach. She might also form an unlikely friendship with Ichigo, and they could combine their powers in unique ways to defeat their foes.
One possible plot could be that a magical accident transports Sakura into the Harry Potter universe. She could use her ninja skills, like her chakra control, to help Harry and his friends in a new kind of battle. For example, in a fight against dark wizards, Sakura's medical ninjutsu could be used to heal the injured wizards quickly, which is something not common in the wizarding world. And her physical combat skills might also come in handy when they face opponents up close.
One plot idea could be that the reborn character uses their modern knowledge to quickly advance Sakura's medical ninjutsu skills. For example, they introduce new ways of diagnosing and treating that are not yet known in the Naruto world. Another idea is that the reborn character tries to prevent some of Sakura's heartbreaks, like her unrequited love for Sasuke in the beginning. They could also team up with Sakura to create new jutsu combinations, using their unique perspectives.
One plot idea could be that Sakura somehow acquires a Sharingan, perhaps through a scientific experiment gone wrong in the Hidden Leaf Village. She then has to learn to control it while also dealing with the suspicion of her fellow villagers.