The Ethereal Domains - Chapter 1956: The So-called Destiny

Just as a gamer found an overpowered skill book called ‘Item Upgrade’ in the hottest virtual reality role-playing game on Earth, something happened to the game’s system, causing his soul to leave his body and go to another dimension. Common sense dictates that he would be born anew then become the greatest overlord of this world by making use of his advanced knowledge. Not in this case! He was already dead. Only some fragments of his soul and that skill book managed to get into that dimension and merge with an ordinary common youngster called Bai Yunfei.

This was the enormous Tianhun continent, where humans could be said to have no limits. There was a group of humans here who could cultivate the power of their own souls then control their bodies, the natural elements and even other people’s souls with that power! These special beings were called — soul cultivators. Come witness how the several fragments of the dead inter-dimensional traveler’s soul and that skill book, which was not governed by the laws of this plane, were going to help Bai Yunfei become a legendary soul cultivator and craftsman!

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.

Li Xiao Yao left S.W.A.T to become an ordinary security guard. While working, he happened to enter the VIP room and found Lin Wang Er still in the middle of changing. As revenge, she took him on a ride and kicked him out of the car.

After hours of walking, Li Xiao Yao finally managed to get back home just to be kicked out of the house. He then got an offer from his previous supervisor to become the bodyguard of the Tian Xi group CEO’s daughter both in game and in reality. But unknown to Li Xiao Yao the girl was actually…

- Description from Novelupdates

What happens when a scientist from a futuristic world reincarnates in a World of Magic and Knights? An awesome MC is what happens! A scientist’s goal is to explore the secrets of the universe, and this is exactly what Leylin sets out to do when he is reincarnated. Dark, cold and calculating, he makes use of all his resources as he sets off on his adventures to meet his goal. Face? Who needs that… Hmmm… that guy seems too powerful for me to take on now… I better keep a low profile for now. You want me to help you? Sure… but what benefit can I get out of it? Nothing? Bye. Hmmm… that guy looks like he might cause me problems in the future. Should I let him off for now and let him grow into someone that can threaten me….. Nahhh. *kill*-

Alternative: Leylin is transported from an advanced technological era into a medieval world— except there’s magic. Equipped with “only” his quick wits and an A.I. chip fused to his soul, he sets out to become the most powerful magus the world has ever known. In a land divided into the Light and Dark Magi, the weak can either be cattle or disposable slaves. Only the strong can determine their lives, and only they have the luxury for virtue. Yet strength is only a tool for Leylin, like any other. His goal, in the end, is his own.