MTL - Wanderer of Myriad Worlds - Chapter 3 checkerboard

Jiang Su transmigrated.

He transmigrated into a BL harem novel as the novel’s main character, jianghu’s number one beauty, who bewitches the masses with just his face, then is subjected to shame, humiliation, and infamy at the end.

To prevent this from happening, Jiang Su diligently practiced his swordsmanship. But then he suddenly realized…If he is still single when the original storyline ends, he will be forced to return to his original world.

Jiang Su: ……

- 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.

The world was consumed by a vile corruption brought from beyond – the sun dimmed, and life as we know it was almost extinguished.And yet it was not the end but merely the beginning.Long after the disaster, a lone survivor awakens with a newfound power to wield the divine flames and many questions about the past. He embarks on a long journey to burn the rot away, discover what's left of the old world and maybe, just maybe, ascend to divinity.

What did death feel like?Ezekiel didn't want to remember. He wished to never experience that void expanse of nothingness ever again.Luckily he had been reincarnated into a world with magic and the sorts. But as a Mechanic!Watch as Ezekiel defies his manaless destiny by walking the path given to him by that Being as a Mechanic born to rule over all.He had been an ordinary person in his last life but he refused to allow that term follow him into the next.“I can still become someone important. Not as an Awakened from Taia, but as a Battle Mechanic from Earth!”