Tensei Ouji wa Renkinjutsushi to Nari Koukoku Suru  

The Reincarnated Prince Becomes an Alchemist and Brings Prosperity to His Country, 転生王子は錬金術師となり興国する

As the third prince of a small nation, Hero discovers his talent for alchemy, which is forbidden in his world. By combining his knowledge from Japan with his newfound powers, he aims to save his country from extinction. Through his unique combination of modern knowledge and alchemy, he transforms his nation into a prosperous one.

Tensei Ouji wa Renkinjutsushi to Nari Koukoku Suru has been published digitally in English as The Reincarnated Prince Becomes an Alchemist and Brings Prosperity to His Country by Square Enix through Manga UP!