My Beloved Dog is the Strongest in Another World - Chapter 990

She, a 21st century mercenary queen, had crossed over into a tragically betrayed body of a waste. Waste? She will show them what it means to be a waste! Betrayed? With the Ancient Manual in her hands, she will astonish all the despicable men and cheap women!

It’s said that the prince of virtue had almighty martial arts. It’s said that the prince of virtue had the most handsome appearance in the world. It’s said that the prince of virtue was brilliant. But all was legend! A fire ruined his wonderful appearance and his legs. Even the talented bride under their marriage agreement were replaced furtively. Ye Liu-li was his bad-luck substitutive princess. She went a long way to graduate from Medical University and had her internship with pain and joy. Who knew that in order to save a suicide patient, she fell off the building and crossed time into a “chessman” of prime minister. She had also been married to the disabled prince replacing her elder sister. On the wedding night, when most other couples were having their romantic night, she was thrilled. It didn’t matter. Revenge never came too late. She would never let go of any of them who entrapped her or harmed her.

- Description from Novelupdates

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.

Ethan Carter never thought much about heroism—until the night he pushed a girl out of the way of a speeding truck and felt cold steel and shattering bones instead of pavement. He expected to die. Instead, he woke up in a hospital, completely healed, with a strange blue screen floating in front of him.[System Activated.][Welcome, User. Your journey begins now.]At first, he thinks he's hallucinating. But when his body starts changing—his strength skyrocketing, his reflexes sharpening—Ethan realizes this is real. The System grants him quests, skills, and rewards, pushing him to break human limits. And yet, there’s more. Locked away in his interface is something called *World Travel*—but it remains inaccessible, its conditions unknown.As he grows stronger, Ethan catches the attention of powerful forces—some eager to recruit him, others determined to stop him. And amidst the chaos, women drawn to his power and charisma begin to enter his life, each with their own mysteries.But one question haunts him: *Why was I chosen?*The answer lies beyond this world. And when the time comes, Ethan won’t just step into new worlds—he’ll conquer them.