MTL - Age of Elves: God-Level Landing - Chapter 272

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.

“O, Hero!” With that cliched line, Kazuya Souma found himself summoned to another world and his adventure–-did not begin. After he presents his plan to strengthen the country economically and militarily, the king cedes the throne to him and Souma finds himself saddled with ruling the nation! What’s more, he’s betrothed to the king’s daughter now…?! In order to get the country back on its feet, Souma calls the wise, the talented, and the gifted to his side. Five people gather before the newly crowned Souma. Just what are the many talents and abilities they possess…?! What path will his outlook as a realist take Souma and the people of his country down? A revolutionary transferred-to-another-world administrative fantasy series starts here!

(Marriage first, love later, short-lived parents, 1v1 double cleanliness)

Du Jingyi braved his fate and married into the Duke’s mansion, becoming the daughter-in-law of a wealthy family.

The husband is Shang Shaoyu, the most popular god of war in the Daxing Dynasty at that time, but it is widely said that he is known as a wife-suppressant.

I thought it was a match made in heaven.

Unexpectedly, on the night of the wedding, Shang Shaoyu only had time to lift his hijab, leaving a sentence of “Cezhou is in danger” and left in a hurry for three years.

After the master returned to court, he remembered that he had a lovely wife in his house.

I thought she had been wronged, but I found that my beloved wife hiding in Xitang Courtyard was living a better life than anyone else.

Everyone in the Duke’s mansion was going through so much trouble, but she was the only one who was pampered…

Du Jingyi just wanted a stable retirement, but he was forced to kill everyone in the back house.

First, half of the bed was given away, and then someone squeezed into my heart for no reason.

Just before her fall.

The general, who had a hard face and a cold heart, had a gentle and charming smile.

He whispered in her ear: Madam, please have mercy…

- Description from novelbuddy

Bibi Dong, once the powerful Supreme Pontiff, never expected to be reborn—especially not as someone else's martial spirit. In this new life, she finds herself bound to a young soul master with great potential but little knowledge of the powerful spirit within him.As Bibi Dong guides her host, she must confront her past mistakes and figure out why she was given this second chance. Is it to correct her past, or is there something more at play?