Legend of Fu Yao - Chapter 2 - 17 Years Later

A young man dies tragically while trying to stop a robbery—only to awaken in complete darkness, lost between life and death.As his memories return, he discovers that he’s been reincarnated into a new world brimming with magic, Soul Weapons, and mystical powers. Reborn as Ares into a loving family, he quickly realizes that this world is far from peaceful. Armed with an SSS-Rank Trait and a Unique Ability, he faces every challenge head-on as he searches for his purpose in this strange new reality.

A mental patient, or a born policeman?

A peerless genius, or a master of crime?

There are cops who are least like cops, and there are criminals who are least like criminals.

Neither good nor evil is absolute.

It is a grey world we live in.

- Description from Novelupdates

This novel is also known as From The Start, I Traded A Galactic Warship

After getting a trading platform three thousand years later, everything in the world has become an antique, worth a thousand gold.

But it was also learned that three years later, aliens invaded, human beings fell, and the dark starry era began.

In this era of unprecedented change in tens of thousands of years.

Shen Shi decided.

First trade a space battleship, and then talk about it.

then–

Battleships come to the world from outer space! Global shock! Starry Sky Era, open in advance!

- Description from novelbuddy

In a world where its inhabitants can destroy a city wall single-handedly, the empress has a kirin as her pet, and the imperial palace of Great Xia has a pool containing a dragon. There is also a Sword Mountain where spirit swords occasionally leave in search of a master .