One Piece: I'm Destined to Be the Son-in-Law King! - Chapter 225: I’m Waiting For You, CP0!

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.

Exploding stars with one punch, extinguishing the sun with breath, crossing the universe in an instant, Retinazer destroying everything… This is the Superman gene!

In the future world, human genes will mutate, and the awakened ones who control various powerful forces will quickly dominate the world.

Awakened people can imitate powerful beasts such as tigers and leopards, and can also control terrifying elements such as wind and fire, and can even extract souls and edit memories…

The traverser Qin Mo awakened the superman gene when he was 23 years old, and he could gain attribute points by absorbing the energy of the sun, gradually adding points to unlock the powerful power unique to superman.

So he went to work every day like this, touched fish, basked in the sun, and added points.

Before he knew it, he realized that he was going to be invincible…

Qin Mo: “I’m sorry, but in the face of absolute power and invincible defense, everything you have is nothing but bells and whistles.”

- Description from novelbuddy

[The Demon King is Dead], a story in which the Demon King got immediately killed in the Prologue. I became the ‘Demon Prince’ of said novel.

…Help me.

I was reincarnated as the supporting character of a novel. As a wingwoman in a depressing romance novel titled at that. Romance is out of the question, and the future of my family is ominous because of debt. I was going to become a civil servant to gain some of the splendor I never got in my last life…but the male love interests are acting kind of strange?! “Just think about it, does Shushu look like someone who would blush and act shy?” “Wow…….that would be great.” Cory said as he stared at Hylli in a daze, and Yves frowned and whispered to himself. “Should I just kidnap her…….” Swan wrapped his face with both of his hands and stayed quiet. His face turned bright red. The blush turned his ears red. Why are you guys fooling around, you’re supposed to be obsessing over the heroine. The story of Shuraina West, Shushu’s reverse harem academy survival. Note: Ojakgyo means wingman/woman!