STRIKER: Independent Beast Tamer - Chapter 365: Part 2: Auction comes to an end

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.

Blue sky, white clouds, lazily lying on the beach, while feeling the gentle breeze coming from the sea. Hounds at the side with marine animals chasing each other around. Cups of unrivaled wine from his personal winery with cuts of prime A grade steaks readily around. For others, life is all about pursuing money, power, and fame, but for Jiang Hai, this type of lifestyle is what he constantly dreamed of.

- Description from Novelupdates

Large-breasted, horny alien Empresses rule the galaxy. Julian doesn’t mind.He’ll go through every last one of them, fucking, conquering, if that’s what it takes to burn it all down.The Imperium of Archos invaded his planet.They razed it to ash.They killed the only girl he ever loved and then......left him to die.But then he found the Exion System, an ancient alien device built to make conquerors, not heroes.It bonded to his body and made him:THE GALACTIC KNIGHT.He’s not here to play hero. He’s here to burn the Imperium down.[Apocalypse System Activated]Host recognized: Galactic Knight.Command Authority: Unlocked.[Initiating Galactic Path.]Julian rises.He becomes a planetary governor.Then a warlord.But he’s not stopping there.He commands mech armies, crushes resistance, and spreads his reach across galaxies.Alien warlords, monolithic ugly monsters and cosmic gods will stand in his way, but they won’t stop him, he'll tear them to pieces!Planets of rivals will fall. Empresses will moan.And somewhere at the end of this blood-soaked path, the monsters who ruined his life will scream louder than anyone.They wanted war.He’ll give them hell.And he’ll make sure they watch him become the apocalypse they awakened.[CAUTION!][STRONG SEXUAL CONTENT.][BRUTAL, INTENSE AND BLOODY BATTLES]

Reborn in 1992, he supported the college student wife Ben and Shuo to study in a row, but she was not allowed to* after ten years of marriage, and she was scolded for peeking when she was washing her hair!

“You’re my wife, what’s up with you washing your hair!?”

“Sneak peek?! You gave me that stealing word!”

“divorce!”

He Hongchang slammed the door into anger and slammed away, but he plunged into the mouth of the hurricane where pigs can take off, and became a trend-setter of the times!

- Description from novelbuddy