Zhan Yue - Chapter 624: you look noob

Syn, a dedicated guard in service to the ninth-in-line princess of a vast space station called “kingdom”, finds his life turned upside down when their ship is suddenly attacked by space pirates. Amid the chaos, Syn is shocked to discover that the leader of the pirates is someone from his past—a person he knows all too well.# Has femdom elements.

What’s worse than finding out you’re that Louis XIV when you’re a baby?

Of course there is, for example, it’s still a magic version.

- Description from novelbuddy

5 years after the world changed, the final boss appeared.

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.