Mages Are Too OP (WN) - Chapter 798: It’s Because I’m Too Strong

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.

Civilization is destroyed and records lost. Only Dudian survives in a cryogenic sleep. Three hundred years later, Dudian wakes up and must become Dean to survive. Who can he trust in this world overrun by monsters without and within?

After dying from a strange terminal illness, Ling Lan was reborn into a world 10,000 years into the future. Although she dearly wished she could just live a peaceful and uneventful life in her new healthy body, fate had other plans…

Forced to disguise herself as a boy just so she could inherit her deceased father’s premium military benefits, Ling Lan’s journey to adulthood was full of challenges. After much difficulty, she finally turned sixteen when she could drop the charade. But before she could grasp her newfound freedom to get married and start her own family, a twist of fate results in her being thrown into the Federation’s top military boys’ school.

With these twists of fate, Ling Lan had little choice but to walk further and further down a path of no return, one of cold and aloof dominance…

- Description from Novelupdates

Takebayashi Ryouma, a 39 years old man with hidden past, found himself in a strange white room. The gods tell him that he has died and that they are sending his soul to a different world, a world where magic exists. After living alone for 3 years, his gamer soul loses its common sense and starts along crazy routes.