My Pick Up Artist System - Chapter 340 Valentina’s sneak attack

A young boy named Chen Zong got lucky and found a mysterious Sword Seal. With the help of it, he rose to be a God in Sword who defeated innumerable top talents in all universes from a remote borderland.

- 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.

Living carefree at home is the greatest shortcut—- My house is the world’s greatest magic power spot, that being the case both my house and I were summoned to another world by some guys who were aiming for it. However, I’ve been living in this place for many years and my body is, apparently, abnormally overflowing with magic. Due to some unforeseen circumstances by those guys who summoned me, they quickly ran away. Be that as it may, there are some ill-mannered people who covet the magic leaking out of my house. I won’t give up my house to those people! I’m going to wield my power as I please!

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.