Eternally Regressing Knight - Chapter 543 - A Night Stroll and a Meeting

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.

Jiang Bai woke up one day and found with shock that he had transmigrated to a parallel world that is similar to Earth. There, he was granted a cheat system to help him forge the path of a tyrant in this new world. He was now stuck in this parallel world body, the body of a weak and cowardly person. Join Jiang Bai as he rose to the top in this new world!

- Description from Novelupdates

“I can’t do it anymore. Stop it…I can’t take it anymore!” The second young master stopped in his tracks and raised his brows as he stared at Miss Jiang. “All you had to do was jog, so—”

Hasami Tatsuro and Yashiki Ai, two ordinary teenagers, experienced an earthquake while on the way home from school.The earthquake cracked space and transported the two to another world.Landing in an unknown forest, the two initially began to grieve. However, unbeknownst to them, a system had installed itself into their bodies, granting them the ability to gain skills and statuses.Hasami Tatsuro obtained the “Level Eater” skill. “Level Eater” allowed the host to devour others’ levels/skills and make it his own.Yashiki Ai obtained the “Valkyrie” skill. “Valkyrie” allowed the host to obtain and use any offensive skills from different classes, without the need to specialize.With their cheat skills and teamwork, they managed to venture out of the forest and explore the new world.This is a story of two ordinary kids.