Valkyrie's Shadow - Chapter 22Winter’s Crown: Act 2,

The impostor Necromancer, with inferior forces, is hunted and rejected by others.The genuine Necromancer, with countless skeletons, becomes a ruling sovereign.After obtaining the Double Doors, Wu Heng discovered that his world was overrun with zombies.Plan A failed, and thus began the implementation of plan B for survival.Wu Heng chose to become a ‘Necromancer.’Summoning undead is forbidden in this alien world? The post-apocalyptic planet is full of potential soldiers.Impossible to survive in a zombie-filled world? Then let me live and learn skills in this alien realm.Hence, an undead army armed with modern weaponry made its debut in this world.A calamity engulfs the world, a million skeletons rise.The Dead Bone Dragon, Undead King.(Double Doors + Necromancer + Magic + Fantasy World + Undead Catastrophe.)

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.

Zhen Lang and Gu Jing have been childhood enemies for over twenty years and pretend best friends in front of their parents. Zhen Lang and Gu Jing’s source of happiness is defaming their enemy (each other) at every opportunity, dreading the day their parents’ match-making dream comes true.

Jiang Xinyu transmigrates into the 1950s without parents. In a time of famine with nothing to eat?But she just wants to live the life of a happy-go-lucky slacker...So she has to roll up her sleeves and fight!Carrying space, full of blessings!Heaven's favor, what you think is what you get.While others starve, she gains weight, determined to live out the luck she didn't have in her previous life.