Sexy Isekai: One Piece Most Wanted - Chapter 36 - : Smart Isekai and Queen’s Gambit

Chen Yan travels between worlds, ending up becoming an honorable prince in a medieval fantasy world. Yet this world was not quite as simple as he thought. Witches with magical powers abound, and fearsome wars between churches and kingdoms rage throughout the land.

Roland, a prince regarded as hopeless by his own father and assigned to the worst fief, spends his time developing a poor and backward town into a strong and modern city, while fighting against his siblings for the throne and absolute control over the kingdom. Join Roland as he befriends and allies with witches and, through fighting and even farming, pushes back invaders coming from the realm of evil.

- Description from Novelupdates

Athen had always lived a solitary life, as without any family or friends, he struggled to survive in his poor, forgotten hometown. The only escape from this grim reality came in the form of tales of magic told by rare visitors from the distant capital.That was, until one day, Athen discovered that magic wasn't just a dream. It was within him.With his newfound power, Athen completed a desperate heist, stealing a priceless diamond. But his triumph was short-lived when he realized the diamond was a fake.Yet... what seemed like a cruel trick turned out to be a blessing in disguise, for the fake diamond held the key to unlocking Athen’s greatest desire: the chance to truly learn magic.

Wang Zhong arrived in an alternate world and became embroiled in this world's global war.What he gained was a cheat, akin to a real-time strategy game's overhead perspective, and he could even see through the eyes of his subordinates' units!So, he decisively started micro-managing, “Shift the machine gun position five centimeters to the left! Place the anti-tank cannon in the forest on the right!”Three years passed in this manner, and Wang Zhong looked at the marshal's baton in his hand, then at the double-headed eagle flag behind the emperor's envoy.“In my hometown, there's an old saying, 'Princes and generals, are they not sprung from the masses?' Envoy, do you know of it?”