The Guide is Actually a Body-Switching Esper [BL] - Chapter 34: This Is Not a Drill

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.

Knowing she married a wrong guy, what would she do to deal with the subsequent marriage lives?

In order to pay for her brother’s medical expenses, she had to replace her own sister to marry the rich family's elder son . She always thought she was married to the elder one, but she did not know her husband was nominally the younger son He Yi Ning.

He Yi Ning, the real heir of the rich family, the ruthless business emperor, the ruthless workplace tyrant, and her sister’s dreaming husband. When she found out that the person who married her was He Yi Ning, she stunned and asked, “Shouldn’t i be your sister-in-law?” He smiled charmingly: “Are you unhappy with your husband?”

This novel is also known as Mr. Mayor Please Be Kind

She is an old spinster of average status. He is young and powerful, achieving status as a high ranking official of River City within a span of just a few years. She had a deep love, but being unable to endure the harsh reality of life, she left. He had also loved once before, but he had been suffered betrayal from his girlfriend and friends, he delayed his marriage.

Having exchanged a few coincidental glances with him, she mistakenly assumed him to be her blind date, and without asking any other questions, she directly inquired him: “Do you want to come with me to get a card (marriage book)?”

He recognized this woman, and holding her with a feeling that was neither love nor hate, pleasure replacing surprise, he nodded: “I’m free in the afternoon!” He had not corrected her.

As per martial business, she offered him an agreement, calmly stating: She will agree to roll the bed sheet once a week! He quietly raised an eyebrow, mouth half-smiling, and flamboyantly signed his name. So because of this agreement…

“Wife, it’s late, let’s get some rest,” the man stated. The woman looked in to his eyes, nodded, and turned off the bedside lamp. In the darkness, a pair of large hands probed into her clothes, caressing her skin like satin. It was a beautiful night.

On the second night: “Wife, it’s late, let’s get some rest, ” the man stated. The woman looked in to his eyes, nodded, turned off the bedside lamp and lay down to sleep. His dark, large hand reached up to her again and slid into her clothes, probing her smooth skin until it was then suddenly caught.

“What are you doing? ” the woman asked coldly.

”There is a marital agreement to fulfill! ” the man said, take it for granted, and then pressed on top of the woman. It was a spectacular night.

The next morning, the woman who was brimming with an aching waist and grief, came out from the study room with eyes wide open, angrily said: “Su Yicheng, you crafty Official!”

The agreement read: marriage, rest once a week!

Love after marriage, warm and spoiled.

- Description from Novelupdates

A prestigious senior mechanical engineer in the industry, Xu Yi was sent to a world dominated by magic.

In a world with an almost non-existent industrial system, how can Xu Yi display his value?

When magic collides with modern technology, when magic merges with machinery, that is the beginning of this story.