So, whenever Sarada Uchiha will use her Mangekyou Sharingan while using the strength of the hundred seals jutsu. Whatever kind of damage her eyes will suffer they will at the same time and almost instantaneously her eyes will heal themselves. This way she will become the first Shinobi and Uchiha to use Mangekyou Sharingan without harming her eyes.
Now, if she gets a strong genjutsu ability through her Mangekyou Sharingan like that of her uncle, Itachi Uchiha or Shisui Uchiha. Imagine if she has a similar genjutsu ability like that of Tsukuyomi or Kotoamatsukami, she would be unstoppable as her eyes will not go blind no matter how much she uses her Mangekyou Sharingan.