The Farmer's Eldest Daughter Has a Spatial Pocket - Chapter 671 - : This is Milk Tea

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.

Branded as the last remnants of evil.Once known as Cero Restes, now living under the name Gabby Magus walked into villain’s path. He swore to hunt every hero’s affiliated with the Dukedom of South in the kingdom of La Magia.Through a web of lies, manipulation, and ruthless strategy, he will rise—not as a savior, but as the villain hidden within the hero’s party.

Q: How would you approach your target?

Tiger Tribe:
Jiang Yu (excited): “Cure him, give him medicine!”

Future Mecha:
Duan Jingzhe (at a loss): “… umm … feed him expired nutrients?”

Ancient Court:
Donghao Yang (banter): “Follow nature’s example and flirt shamelessly.”

Next unlucky protagonist: “…”

This is a collection of three short stories in which each protagonist crosses to another world or is reborn.

- Description from Novelupdates

One day, Yoichi who grew up while not knowing his parents has received the news of his father’s death. His father left behind a testament——which said he is to pick only one out of five ‘little sister candidates’?!