Two people from different time and space meet unexpectedly. She discovered that someone similar to her brother was actually the teacher here.
Slowly, more and more people need to be protected, including the village. "Okay, I would rather be condemned for my race than to protect this place, my teacher and my companions to the death."
She accidentally got the Sharingan, "As long as you inject your own life, you can save everything!"
This is the most ridiculous legend in the history of Konoha! (The story took place after the Fourth World War)
(Assuming Kakashi's Sharingan was not dug out and Obito was not dead.)