An Empress's Return to the Present: The Real Young Lady's Strong Comeback - Chapter 439: Preparing for Reunion Dinner

In her last life, she was miserable and ordinary. This time, she got into the fashion and was reborn in another world. She was still the same person… even with the same body and face. What was the point of reincarnation? A childhood companion? He always pulled her hair and made troubles for her? A handsome boy? The boy never looked at her and was 15 years older than her! A prestigious teacher? The teacher spent his days eating and drinking, coaxed, played tricks, and controlled others… Too scary and better run away? No no no, such a challenging life was bound to be wonderful! Now let me take you back to the 70s and live a fast life!

- 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.

The prospective college student Luo Ji, who is enjoying the last summer of the third year of high school, has undergone earth-shaking changes at this moment after accepting the invitation of the game friend and becoming the player of the game of “Civilization Rise”.
This is a war game between the world and the world, and it is a fierce collision between civilization and civilization!
To annex the five continents, sweeping across the three oceans, and see how Luo Ji led his people, in this powerful enemy look around, the battlefield of the heroes to fight for a battle to the most powerful imperial civilization!

- Description from uukanshu translation

She was the most arrogant assassin in the world in the twenty-first century, yet in the end, she was unintentionally killed by her senior brother, resulting in her traveling to Bingzhou continent. The first step after she opened her eyes was to crawl out of the fecal drain and throw the woman who schemed her into the fecal drain. However, at this critical moment, she met a cold and arrogant beautiful man. Looking at his disdainful expression … She would always remember the words of this proud and aloof man. “Once my beloved wife has my child, I will seize Ming You Nation’s land for you and our son!”