Naruto: The Mist Within - Chapter 1 - : In the Hidden Mist

She was the Eldest Legitimate Daughter of the General's Mansion, treacherously harmed and died a miserable death. Perhaps moved by pity, heaven granted her rebirth. She returned to four years earlier, not only possessing heterochromia that allowed her to see what others couldn't but also equipped with a portable space. She vowed to make those who hurt her and her mother pay in this life.He was a Prince with a Different Surname from Moli Country, holding military power and commanding awe in all directions. It was said that he had conquered most of Moli Country, and even The Emperor showed him deference. Legend had it he was a bloodthirsty prince who killed without blinking an eye.One day, she encountered a ragged but handsome man on the street, who chased after her, shouting, “My wife, my wife.”The woman said, “Damn it, who is your wife? Aunt isn’t even engaged yet! Go where it’s cool and stay there.”The man responded, “You are my wife, and I've decided to follow you for life.”“A feel-good story, both leads are strong, a pampering love story with 1v1 romance.”

I wasn’t hit by a truck, nor was I struck by a thunderbolt, yet here I’m inside Hunter X Hunter world, and I even have a system, but it’s really a weird one, it always gives me these kinds of choices:

【1：Join the Ryuudan. Reward: Magma Fruit.】

【3：Destroy the Ryuudan. Reward: Ice Fruit.】

【2：Ignore the Ryuudan. Reward: Fire Fruit.】

Allan sighed, “The problem is I’m really an indecisive guy…”

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.

A good-for-nothing man married a beautiful girl but was kicked off the bed on the wedding night. Furiously, he wrote a bill of divorce and ran away.
He was schemed a car accident in which he nearly lost his life. However, it turned out to be a blessing. He swallowed the soul that passed through the outer world, thus obtained superb medical skills and martial arts.
Later on, with the silver needles and invincible martial arts, he embarked on the road of counterattacks and was committed to his great dreams.

- Description from Novelupdates