Official Career Storm - Chapter 1235:

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.

Kota Sakamoto—virgin weeb, social reject, and hentai game addict—gets sucked into a perverted dungeon world straight out of Carnal Labyrinth EX, the 18+ erotic strategy game he secretly 100%-cleared.The catch?All eight of his hot classmates and their strict MILF teacher got dragged in with him.The other catch?They hate his guts.Worse still, this dungeon world is exactly like the game—every level a twisted, orgasm-fueled survival puzzle where failure means death by overstimulation, lust-monsters, or trap-triggered climaxes that literally drain your soul.He’s the only one who knows how to survive.They either listen to the virgin... or moan themselves to death.Bondage plants, lewd slime traps, fetish trials, and orgasm boss fights await—and the only way forward is obedience.What starts as reluctant cooperation turns into obsession, as each girl slowly falls for the boy they once mocked...…the virgin who’s now their dungeon master.

Varian only wanted to end the war with the Abyssals and bring peace so that no one would lose their dad like he did.

Known as the youngest academician-level senior engineer, Zhao Guoyang was reborn in the 1990s. In this era of economic globalization, with his extraordinary wisdom and extraordinary insights, he created one miracle after another and became a name that shocked the world!

Wisdom is condensed every bit, brilliance is created by sweat, and witness the rise of a great power!

- Description from novelbuddy