MTL - Love Rival Romance System - Chapter 59 Stick to you

Shuu is a member of the literary club that can’t write. One day, he gets a mysterious message on his phone from a girl called Eina, and from that impulsive contact, they begin to exchange messages. They talk of things like their shared interest in novels and grow close. However, when they try and meet, they discover a shocking truth. Eina lives… not in the present, but five years in the past! How will their love develop, parted by five years of nights…!?

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.

Once she transmigrated over, Li Haitang, an elite female doctor from the big city, is demoted to a pitiful little cabbage whose parents have both died. She is surrounded by extreme jackals, wolves, tigers and panthers family and relatives. What? She is sold to a half-dead body that is going to be buried in the ground. Has she been sold to an old man with a heavy taste? The only way to escape from the arranged marriage is to pack a bundle wrapped in a cloth! Who would have thought that on the way to the wedding, she meets a wild man who is feared by everyone in the village? The wild man has three treasures, he is hardworking, spoils his wife and has good stamina! His pectoral muscles, abs and mermaid’s line are all there.

Jian Wushuang was reborn in adversity. In order to get his revenge, he began to cultivate Heavenly Creation Skill. With the help of the Heaven defying cultivation method, Jian Wushuang gradually grew into a peerless genius from an ordinary practitioner. With a sword in hand, no one is his match. Using his extraordinary Sword Principle, he killed all his opponents and eventually became number one Sword Master from time immemorial.

- Description from Novelupdates