Naruto: I am the Hokage - Chapter 67: Asuma: I Hate the Sarutobi Clan!

In the foreign world, the martial artists dominate the world and the sword of the emperor controls the fate of hundreds of millions of lives! Long Yu, the number one killer on Earth, after dying, takes rebirth in this new world in an aristocratic family of martial artists but faces rejection because he is unable to practice martial arts.

- Description from Novelupdates

Lin Ping'an traversed to a High Martial World, where the Ten Thousand Races invaded, leaving the Human Race weak and on the brink of danger. At this critical moment, he awakened the Civilization Master System.He simply created countless speedy Demonic Cultivation Techniques that spread widely, causing the Ten Thousand Races to exclaim how truly bizarre they are.[ Painful Demon Body ]: The longer the cultivation time, the faster the Qi Blood grows, but the more painful it becomes.[ Qianyuan Burning Life Technique ]: Burns life to gain strength, living like a summer flower, blooming with momentary brilliance.[ Celestial Demon Dissolving Technique ]: Burn all of oneself to unleash the strongest combat power.[ Abi Dao Three Blades ]: Bound by Demon Thought, eternally falling into Abi, the three blades extinguish ghosts and gods.[ Heaven-Defying Seven Demon Slash ]: Soul destroyed with no regrets, protecting the Human Race, slash slash slash slash slash slash slash.[ Life-Burning God-Slaying Arrow ]: Soul as the guide, life as the arrow, one strike for the fall of the demon emperor.Emotionless Swordsmanship... Dao Heart Demon Planting Technique... Blood God Technique... Sunflower Manual... Blood Escape Technique... Soul Destruction Nine Palms...

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.

“According to prophecy and scientific calculations, the entire world will see temperatures drop to minus forty degrees within three years, and even the earth's core will be frozen within three hundred years.”“What should we do?”“Gather all our strength, build a shelter together with unwavering unity. In the face of disaster, we must stand united, and everyone needs to do whatever they can to ensure a future for humanity!”“But what if someone refuses to work and just wants to eat and be lazy?”“Then let them die! Activate the alchemy golems and large robots, we do not support idlers!”Set in a scenario similar to Frostpunk, with fantasy elements and a steampunk background, viewer discretion is advised.