MTL - Bourne: Command and Conquer - Chapter 177

One day, Raizou ​​Takakura, an average salaryman, had a Heart Attack and his life ended that day.

But, he got a second life, in a different world.

Reincarnated with strong skills―― wasn’t what happened to him, instead, he was reincarnated as a foot soldier in a small country, Highserk Empire, which was surrounded by large countries.

With a new name, Walm, he was thrown into the frontline of war.

Covered in blood and the stench of death, along with his comrades, he was slipping through life-or-death situations.

An adventurer party with members that could use powerful magic, transferees with overwhelming power called the “heroes”.

In a deadly battle with them, Walm gradually developed his talent as a warrior which would’ve never awakened if he were to stay in times of peace.

While his eyes becoming dark and muddy over time――

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 worst student of Westroad Academy. The disgrace of the Blake House. A new soul enters the body of Frey Blake, who couldn’t overcome his miserable life and chose death instead. “What’s with this body? I’ll have to work on tuning it from scratch.” The Great Mage Lucas Traumen, with the body of Frey Blake, gains a chance at revenge!

Seven years ago, Shen Qianshu is impregnated with Ye Ling’s child in an accident.
Seven years later, the little boy becomes famous and is thought of as the nation’s son.

When he suddenly sees Ye Ling appear, he greets, “Hello, Daddy?”
Ye Ling watches as the little prince roars, “Where’s my princess?”
Just as Shen Qianshu is preparing to run with her son, she gets pushed down by Ye Ling.

“You can leave if you want, but leave me a princess first. Let’s have another baby!”

- Description from Novelupdates