Stellar Echo: Heart of the Myst - Chapter 1 - : Where am I? But more importantly… Who am I?

I awoke as Violet, a familiar villainess trapped in a shady corporate research lab. Screw this! With my unstoppable cloning technique, I’m getting out of here and going to the Academy to live my own life!

The youngest daughter of the famous Sheng Family who has been lost for seventeen years has returned! Since she was brought up by a rural mute granny, many people think her life has been ruined and can’t wait to see how she disgraces the Sheng Family!

Wen Er girl is unparalleled in beauty, but when people mention it, she has to sigh because she was born dumb. Unexpectedly, one day, the second girl Wen, who fell from the wall and hit Prince Jing’s body, suddenly spoke.

- Description from novelbuddy

A man is reborn into the world of Avatar: The Last Air Bender as a waterbender from Katara's tribe. Best of all, he was the same age as her, and he had a system with him to help.He knows the future and a system that lets him continuously get stronger by completing quests or long-term missions, as well as giving him the ability to copy abilities from others for himself. He will become invincible in the world of Avatar, even more so than the Avatar himself.