Maybe a Fake Gintama - Chapter 80: The Feeling That Only One Person Can’t Think of the Answer When Playing a Guessing Game...

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.

Crossing to a garbage star in the interstellar age, Ji Yu is so poor that she is about to plow the soil and eat it, but… the soil is poisonous and can’t be eaten… There is no way, she can only lower her body to pick up the garbage, sell it and sell it. of……

For example, no one wants such beautiful grass seeds. Pick up a bead and sell it online.

But as soon as I posted it on the Internet, someone made a negative comment: “All the grass seeds and fruits are sold. Are you crazy to think about money?”

A few days later, the man slammed the wall in regret: “Kneel and beg you to sell me one grass seed and fruit, only one! One is fine.”

Ji You said coldly: “Not for sale!”

For another example, these shattered stones on the street are so shiny that nobody wants them. Pick them up, polish them into bracelets, and sell them on the Internet.

The crowd made nasty words: “Broken rocks are all sold, haven’t you seen the money?”

A few days later, everyone wept bitterly and said, “I have no eyes, I am clumsy, such a beautiful and beautiful stone, please beg me for one.”

Ji You said, “It’s gone.”

- Description from novelbuddy

In his past incarnation, Lu Xuan was the youngest Celestial Lord that the universe has ever seen!
An accidental rebirth brought him back to a thousand years before, where the Earth had just begun its spiritual reawakening. When he stepped onto the way of cultivation for a second time, he swore to rewrite all injustices suffered in his past life, and defeat all enemies that dare stand in his way!
Let invincibility be his cultivation and the path he treads. In this life, it is his destiny to be invincible!

Gu Zuo: Are you sick?

Gongyi Tianheng: You have medicine?

Gu Zuo: You’re sick!

Gongyi Tianheng: If I say I’m sick, can you cure me?

Gu Zuo: If I say I have medicine, would you want it?

Gongyi Tianheng: However much you have is how much I want.

Gu Zuo: However much you want is how much I have.

Gongyi Tianheng: Then bring it all out.

Gu Zuo: …

Simply speaking, a scaredy-cat shou transmigrated and had to think of a way to survive. He had a golden finger called Medicine Refining System, but unfortunately, he didn’t have the ingredients needed to refine medicine and level up.

A great young master to an Empire’s preeminent Clan had a super high IQ, but his talent for cultivation was low. Unfortunately, pill refiners were too hard to develop, and weren’t restricted to his personal service. But he could acquire plenty of ingredients.

Two people, one was sick and one had medicine. Therefore, the one who was sick kept the one who had medicine, and everyone was happy.

- Description from novelupdates