Naruto System in One Piece - Chapter 476: Sasuke and the Sound Ninja

In China’s modern martial arts society, Wu Xinghe was history’s youngest grandmaster of martial arts. He was invincible. Because of a strange incident, he was reincarnated as Qin Wushuang, a poor aristocratic boy in an entirely different world with its own set of rules. With his strong will and passion, he began his journey to pursue the highest peak of martial arts!

A tree of 10,000 flowers, the world is the door.
The spells change a lot, but the hearts of the people are unchanged.

- Description from Uukanshu translation

In Ten Heavens Domain, full of respected powerhouses, juvenile Ling Tian accidentally obtained a mysterious iron sword. He refined the Supreme Martial Dao, studied the Divine Spirit Array Laws, fought Ten Thousand proud and arrogant Heavenly Clans, and was undefeated! Seven Feet Sword Tip sweeps away the world, within the Ten Heavens, I am the Supreme God Monarch!

- Description from Novelupdates

Xia Lian, a 21st century military doctor died in an explosion and found herself transmigrated to the body a 12 year girl. Her mother died and her father abandoned her and her little brother for another woman.