With Countless Qualities Bestowed Upon Me, I Shall Ultimately Become Immortal - Chapter 50: Silver Base, Golden Lion

On the surface, she’s a gay high school boy. In reality, she’s the hacker known as Z, who hunts criminals on the Internet. A girl dressed in men’s clothes; a master at playing games, punishing evil, and having the highest skill in seducing girls. When people learned that “he” was actually female, the entire population blew up!

Fu Jiu: “Great Deity Qin, do you have a girlfriend?”

Qin Mo puts down the laptop: “I don’t have one.”

Fu Jiu starts to seduce in a low voice: “In that case, you have one starting now. Me.”

Hearing this, Qin Mo leans over tyrannically.

Fu Jiu is dumbstruck: “Hold on! What are you doing?”

Qin Mo: “Using my privilege as a boyfriend.”

- Description from Novelupdates

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.

An alien race invaded the Earth on June 6, 2128. At the midst of this war, many nations allied with the alien threat and the war nearly wiped out the rebelling humans of the planet. At the edge of mankind's survival, the United Nations Army launched its forces to eliminate the immediate stellar threats that loomed over Earth.

General Seeker Carlean, commander and leader of the mission, risked and gave his life to destroy the immediate stellar threat. The battle was won though Earth lay in ruins. Perhaps mankind will live to see a few years of peace before the alien threat returns to wipe out their existence.

At the immediate aftermath of the stellar battle, the fallen Seeker Carlean awakens and finds himself at aged 17, living the peaceful life he lived 16 years before he died.

So begins a new game in the battle for humanity's survival.

Daniella was ready to pull the trigger when she felt a warm hand touches her hand.