You Practice Immortality, I Farm - Chapter 100: Zhou Tian Star Fighting Sword Array Zhenshan

A high school student that has lived as a mob-character ―― Mimori Touka

He rose from abjection and achieved eternity in glory.
He embraced the prettiest beauties and killed the strongest opponents.
He was able to shift the clouds into rain and cover the sky with one hand.
He could overrun the entire world and go anywhere as he pleased.
He pacified wars and held the world in awe.
He was matchless in the world.
However, his hair turned white overnight for his beloved woman and he was on the verge of death.
He was surrounded by enemies who were trying to take his life.
He struggled his way to become mighty and fought for everything he cherished.
For this age, he was the only king of the Dark World.
His name was a byword for might.
As a man living in the world, his only ideal was to pursue brilliance.

- Description from Novelupdates

Baek Yigang is a son of the Baek Clan, one of the seven great clans of Zhongyuan. Afflicted with the Taiyin Qi Blockage, he is cursed with a shortened lifespan and the inability to collect internal energy. He had been peacefully spending the rest of his days indoors when he was ambushed by a group of masked people. During the ambush, he lost his servant who was like a sister to him. Chased by the attackers, Baek Yigang escaped through a secret underground path. When he came across a blocked path, he decided he’d at least die fighting and picked up a rusted sword that was stuck in the ground…

A con-man and policewoman that are legends of their respective professions suddenly die, then are reincarnated and return to the Tang Dynasty of ancient China as little kids.

Accepting their second chance and forced restart, they choose to use the modern knowledge and specific talents that they have in their previous lives in order to live comfortably in this new life.

- Description from Novelupdates