Sword of Dawnbreaker - Chapter 86 - Bold Plan

When powerless, unfavoured Princess Soleia was arranged to marry the newly titled Duke Orion Elsher, she assumed they would find love eventually.Who knew that her father would send off her husband mere hours later to fight a war?Soleia was left alone to deal with an impoverished fief, a crumbling estate, and spiteful, vindictive relatives of the Duke who all wished to see her gone.She couldn’t leave― there was nowhere else to go. Soleia desperately wanted her husband to return so he could offer her a helping hand. However, when he did, he returned with Elowyn, a woman he claimed was his true love.A woman hellbent on taking her place as the rightful Duchess, no matter what she had to do to get Soleia out of the way.Mistreated, misunderstood, and miserable, Soleia was eventually thrown out of the estate she helped build.Fortunately, when one door closes, another one opens. Unknown to Soleia, a man more powerful than her husband had been watching her, waiting for the right time to snatch her into his gilded cage. Duke Elsher had been foolish to let go― but the crown prince of Raxuvia wouldn’t make the same mistake.***Prequel to Stolen by the Rebel King.

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.

The vast Kunwu Mountains, one hundred and eight thousand. Spiritual ethereal sword rising, sweeping the summits of the nine provinces.

A modern day otaku is reborn in a wuxia world, becoming the little shishu of a little sect. Unexpectedly discovering he has the martial arts trade system of a garbage web game. Through it he can actually exchange for all of the martial arts in Mr. Jin Yong’s novels.

And so, Nine Yang Manual, Nine Yin Manual, Nine Swords of Dugu, Eighteen Dragon Subduing Palms… All kinds of amazing martial arts started to dominate the jianghu of another world…

- Description from Novelupdates