Sakura was content. The war was over, her relationship with Sasuke was almost progressing, and her life as vice-director of the hospital was great. Then why, oh why, can't she have a minute of peace?
Plucked from her own world after a summoning gone wrong from a quirk used by All for One, she was reborn in a universe without chakra, and without her memories. Well...until the accident at 6 where she lost her mother and almost died herself. After her "quirk" and memories finally merged, she was taken by the hero commision and trained to the ground (again, as if Tsunade-shishou's training wasn't enough, hah).
The comission needed a way to discover what happened to All Might and the cause for his efficiency as a hero diminishing, so they sent her to UA to find out why. What could go wrong with Sakura in 1-A? Oh, and did she mention that All for One is technically her father, and Izuku's (not that she really knew the last part) ?
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Or, alternatively, Sakura is reborn in MHA universe as Sensei's daughter and all hell breaks loose.
Art by : Quri000 - https://www.wattpad.com/story/237129412-dibujos-de-sakura-crossovers-%F0%9F%A4%AD%F0%9F%8C%B8?utm_source=android&utm_medium=pinterest&utm_content=share_inline_media&wp_page=media_slideshow_button&wp_uname=Keyli_Otaku&wp_originator=pjFFPp08SWlvqTYsuf6nPMwPGozn5cf6pDvMQbNKjfPhk8QjfyG7dQgsArpLw8dg0AcOCgQF3s4MumR94m1e3inwgbQOHpJCDIb17IiSa1pfIBIYXmGRBAOxvF%2BxeafZ
Kanda Kyoichi transmigrated to Konoha and became a temporary instructor at the Ninja Academy. Fortunately, he awakened the Mentor System.
By teaching others, he could earn rewards.
Thus began Kyoichi's career as a "teacher" in the ninja world.
Shisui: "Sensei's unique interpretation of the Will of Fire has given the Uchiha Clan a true sense of direction!"
Asuma: "The essence of the jade lies in protecting the people, with the advanced leading the way for the less experienced. Only then can Konoha become stronger!"
Kakashi: "He's my life mentor. He transformed Konoha!"
...
Years later, in the memoirs of Kyoichi, now the Hokage, he wrote:
"I honestly just wanted to be a life mentor!"