Black Bellied Belle: Demon Lord, Bite The Bait Please - Chapter 11.1

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.

Ye Xuan transmigrated back to when he was an infant cuddling in the embraces of his nine older sisters. He activated the God-tier Sign-in System.

[You are hugged by your eldest sister, who is the COO of a financial conglomerate. You signed in and obtained RMB100000000.]

[You are fed medicine by your second sister, who is crowned the God Hand. You signed in and acquired god-tier acupuncture skills.]

[You trained along with your third sister, who is a Martial Arts Grandmaster. You signed in and your overall physique improved.]

[You live-streamed with your fourth sister, who is the top news anchor in the country. You signed in and acquired extraordinary good looks.]

……

Ye Xuan could sign in daily!

After staying in the city and signing in for eight years, Ye Xuan had accumulated an astronomical amount of wealth and become a billionaire.

On his eighth birthday, his nine sisters were forced by the grand elder of their clan to get married. Just when everyone had lost hope of turning things around, Ye Xuan hopped down from his eldest sister’s embrace and said, “You’re marrying my sisters off against their wills. Have you consulted me about this?”

Liu Changgong time-traveled to a cultivation world. However, without any talent for cultivation, he was destined to be an average person. So, Liu Changgong simply cultivated for fun. When he was free, he would also do calligraphy, paint, play chess and the qin to pass time…

Once an imperial princess, now reborn among the lowest of s*aves of the nobility.