Is this This Life, the Way I Want...?
From Anime-Planet:
When Erina gets adopted by Marquess Sinor because of her magic abilities, she didn't realize her life was only about to get much worse. After years of abuse and torment from the Marquess, Erina is on the verge of breaking down. Just when she decides to end it all, Erina is visited by her past self: Marystella, the powerful witch who once ruled the entire kingdom. Marystella asks Erina if she could help her reveal the truth behind her death. In return, she promises Erina to make her the greatest sorcerer that the world has ever seen. No more suffering, no more pain; Erina is about to do whatever she pleases with her newfound power!
Six years ago, a young, white-haired orphan named Erina was tested for magical affinity and given an unusually high score, suggesting that she'd grow up to become a powerful sorcerer. She was then adopted by a marquess, Kerman Sinor, who hoped to make use of her powers when they manifested.
Six years later, though, she's yet to start seeing any Nymphs -- as a sorcerer should be able to -- and the impatient marquess consequently views her as a useless leech, and subjects her to physical abuse. She also has an adopted brother, Hevel, who's nice to her on the surface, but intentionally redirects his father's anger towards her to avoid being physically abused himself.
Erina is subsequently visited by the spirit of Marystella "Mary" Feolina, the person she used to be in her previous life. Mary was a powerful sorcerer and the leader of the Kingdom of Feolina, but was overthrown and executed after her kingdom was nearly brought to ruin.
Mary accelerates Erina's magical development -- enabling her to see Nymphs and use the powers of the Water Nymph, Undine -- and promises to make her the greatest sorcerer the world has ever seen. In return, Mary wants Erina to shatter a sacred relic called the Melcurado, in order to reveal the truth behind the events which led to her death.
Under Mary's guidance, Erina leaves the marquess' household and enrols at a magical academy, where she meets the black-haired male lead, Daymond Speroche.