Villainess is being pampered by her beast husbands - Chapter 90 --

I gave them my everything.My time… my strength… my heart.I trained while they slept.I smiled when they laughed.I stayed… even when it hurt.And what did I get?Nothing.They looked at me like I was pathetic.Like, I didn’t belong.Like I was… less.But I... the naive person I am, continued trusting them.They told me to act like trash, fine—I became trash.They told me to act like a scumbag, fine—I played the role.However...One mistake, one single moment...That’s all it took.And they threw me away.But now…Someone else woke up in my body.A stranger, a man who doesn’t know the pain I suffered, but wears my face.Let’s see what he does with it.Because me?I’m done with this life, so to the soul who took over my body...This is your mess now…'Gray'.

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.

Enter a world of superhuman abilities and mysterious organizations as you follow the story of Jiang Bei, the enigmatic founder of the Infinite Alliance.With the power to extinguish stars and melt anything in his path, he is hailed as a god among men and the torch of the Dark Era.But what secrets lie behind his incredible powers, and what will he do to protect his legacy and extend his life?

In his past life, Ethan Steele was an ordinary man living in a modern world—working a dead-end job, struggling through the monotony of daily life, and haunted by regrets of missed opportunities.At the age of 23, his life came to a sudden, unexpected end in a car accident. As his consciousness faded into darkness, he was sure it was over.But fate had other plans. In the divine realm, the God of Fate watched over the balance of life and death.Ethan's untimely death was a mistake, an anomaly that diverged from the preordained path of his destiny. It wasn't yet his time to die, and so, the god decided to give him another chance.“You were meant for greater things, Ethan Steele,” the god's voice boomed. “To correct this error, I will reincarnate you in another world—one filled with magic, swords, kingdoms, and adventure. You shall be reborn, but you will not remember your past until the appointed time. There is, however, a... complication.”By divine error, the god accidentally bestowed Ethan with the Harem God System without having any idea about it.This system is a powerful, reality-bending system that would allow him to charm and seduce influential women to build his harem, growing in strength and power with each conquest.“Your memories of Earth will return on your seventh birthday. I hope you enjoy your life here in this world”And with that, Ethan's soul was transported to a new world.