Still, Wait For Me - Chapter 535: Wild volley

Being poor, weak and introvert, Daniel Lolzwood has always struggled to get a friend, let alone a girlfriend. Who would have thought that one night, a succubus, the most beautiful girl he had ever seen, would come begging him to become her boyfriend? She even gives him a strange system. He can now visit a fantasy world and...Enough with words. I guess it's time to become both rich and handsome while enjoying beauties and revenge..............................Additional tags: [No Yuri] [No NTR] [Adult Content Warning]

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.

Before his death, he was the only sword cultivator in the whole world, who dedicated his entire life to the path of sword immortality.

When he opened his eyes again, the world had completely changed. He began to cultivate the path of sword immortality again, slaying the heavenly way, shattering the universe with his will, and achieving the realm of sword immortality!

- Description from Novelupdates

(following the boat) When a person who can get random superpowers every day enters the world of pirates and joins the protagonist group, what will happen as a result?

Luffy: “Si Guoyi! Lin Bei, let’s jump from the sky again!” Kebi: “Please don’t!” Sauron: “Be sure to leave Lin Bei’s room at twelve o’clock every day!”

Nami: “This bastard, just let me…” Akainu Sakasaki: “Bastard Lin Bei, turn me back into a man!

The old lady used her ability to come to her aunt once! “Big” boys, come and meet your father! “Lin Bei:!!! This really doesn’t exist!!!

- Description from novelbuddy