The Female Assassin Pretends to Be a Lamb in the Campus - Chapter 452: Waistcoat: The Father of the Robot 02

Violet skies, a world undergoing massive changes, a deficient moon, interlinking voids…

Holy Lord, possesses the ability of zodiac signs, dragon charm, can spray high-temperature flames, pig charm, emits laser light from both eyes, horse charm, heals all injuries, dog charm, immortality, rabbit charm, possesses light like or even surpasses light speed, chicken charm, suspended in the air, monkey charm, transform into any form, snake charm, transparency, sheep charm, soul out of body and even control soul, tiger charm, adjust yin and yang, rat charm, grant the ability to move still objects , the cow charm, has infinite power (some abilities are fabricated by me), this article is about the protagonist who has the Holy Lord system, travels through many anime worlds, and promotes his majesty… [Diga (in progress) Hokage (unfinished) Open) Pirate (unopened) Attack on Titan (unopened) Tokyo? Brother Zheng ㄎ Chun? Kai) Conan (unopened)…〕

- Description from novelbuddy

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.

The female protagonist crossed over to become the Venerable Woman Kingdom’s Crown Princess. That’s right, that’s right, holding power and authority and handsome men!

What? She’s has the body constitution of trash and is unable to practice martial arts?

Having finally set her eyes on a good looking man, he turned out to be a snow wolf. Isn’t that just so sad and depressing….. Having captured a good looking man, a certain woman laughed sinisterly. “Remember this. You are already mine, so you have to remain chaste for me. If you do not obey, I will then reject the goods.”

The handsome looking man was stunned with his mouth agape. “You….. You’ve gotten it completely backwards!”

- Description from Novelupdates