Okami Wa Nemuranai - Chapter 51.3

Blue Star has entered the extraordinary era, everything is evolving, and monsters are rampant.

Humans awaken their star souls in evolution to fight against raging monsters.

Zhou Xuan, who was doing odd jobs in the Demon Town Tower, accidentally awakened to an unscientific sign-in system.

Sign in on the ancient desolate beast and gain the power of the wild. Sign in on the weed spirit, and the star soul evolves into the nine-leaf sword grass.

The thousand-year black turtle, the ten thousand-year sea king, the immortal true phoenix, and the sky-swallowing dragon have all become the targets of his registration.

There are countless monsters in the Demon Suppressing Tower, Zhou Xuan signed in silently, and if he was not careful, he would be invincible.

Reborn in the world of One Piece, I, Karl, was granted a unique “Gacha” System. Every five years, I get to smash a golden egg and pull a legendary prize.At age 5, I pulled the [Infinitely Evolving Monster Body]. As long as I keep eating, I keep getting stronger. The seas would soon fear another monster like Big Mom.At age 10, I pulled the [Sealed Mystical Spear]. A weapon capable of converting my stamina into a beam of pure light, capable of annihilating anything in its path.At age 15, I pulled my greatest prize yet. A card from another world... the legendary [Blue-Eyes White Dragon]!At age 20... the world was no longer ready for what I would become.My legend begins in the East Blue, but my destination is the heavens. They call me a pirate, a monster, a king.But my true title is... The Dragon Knight.

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.

Divorced, disowned and down on her luck, Shui Anluo was determined to move on and live a peaceful life… That is, until her ex-husband somehow managed to find out about her baby. Now, he’s insisting that she should move back in with him. Soon, he realizes that he cannot live without her… But the road to marriage is bumpy, and Shui Anluo isn’t too willing to go through with the heartbreak again. Can she take back everything that belongs to her? Will she find the courage to jump in and fall in love again?