Warm Wedding, CEO Loves Me - Chapter 2202

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.

[Cover] NOW HIRING — URGENT — Ghost Story Specialist Corporation Daydream Inc. (Ltd.) Insane Benefits – Come to Work Immediately ※ Note : The company is not liable for any injuries or fatalities that may occur during the course of the employee’s duties. —— A pop-up event for some ‘modern fantasy’ media I loved so much that I even took a precious day off work to attend. On that day, I ended up transmigrating as a character in that very fantasy world. As none other than a newly hired employee at a famous large corporation! A dream job with great benefits, an excellent salary, and even kind and competent bosses. I’m using the information I know about the world to rise through the ranks at lightning speed! Am I happy, you ask? Please, just let me go home. I’m begging you. ※ Note : The genre is horror.

The price for saving the world is the right to rule it. After saving a faraway land, Lyn Rivers was cast back to Earth. Wanting the admiration, prestige, and glory of saving that realm, she forced her way back. But she was forgotten, and someone else claimed credit for her deeds. Now, with the power of a deity of destruction, she desires nothing more than to claim her place in history. To do that she will conquer dungeons, make alliances, destroy kingdoms, and build an empire. After all, why ruin the world when you can bend it to your will?

Once the ultimate Soldier King and a supreme assassin, empowered by a magical Magic Bracelet, had mastered Cultivation, Medical Skill, X-ray vision, and foreseeing the future… became an omnipotent master of pretense. Come, come, come, watch the omnipotent master of pretense teach you a few tricks of pretense.A demonic man who walked out of a major foreign prison, yet married a cold Queen-like CEO wife, leading a life where “you glare at me with displeasure, and I look at you with disdain.”