A Precious Pearl in the Imperial City - Chapter 107

Six years ago, he disappeared silently! After six years, he becomes the unparalleled "God of War" and returns with glory, only to find that he has a daughter whom he never knew of. Looking at his wife and his daughter, he says, "In this lifetime, I'll bring you the greatest honor and glory!”

A piece of divorce paper sent Xia Xinghe into a state of destitution. However, a car accident later, she transformed into a professional hacker with more money than she could ever spend. All those that have belittled, bullied and laughed at me, please line up, I’ll show you what the meaning of face-slapping is! Wait, wait, wait. That guy over there, the ex-husband that I no longer have any relations with, don’t cut in line. What, you want to help me face-slap these people? “Not only that I will help you face-slap myself!” The wickedly handsome man with billions of dollar in estate raised his own palm to slap his own face without reservation!

- Description from Novelupdates

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

Transmigrate to the world of One Piece, reincarnate as Saint Imu; Control the world government and sit on the throne of the void.He obtains the star map of the omniverse and contemplates the sea of dimensions.Gather all individual combat power, military power, financial resources and all material resources to open the star gate, conquer all dimensions, and break the limit of individual power!Unite or be destroyed, how to choose?