Card Game de Sekai ga Horobu Sekai ni Tensei shite Card Shop wo Kaiten shitara, Shuui kara Zensaku Shujinkou da to Omowareteiru

In worlds where card games dominate everything, it's almost a cliché for the fate of the world to hang on the outcome of a card battle. I, Mitsuru Tanefuda, found myself reincarnated into such a world. Thankfully, my dream came true—I became the manager of my very own card shop. In this world, people duel with cards, filled with joy and excitement, and I wanted to watch it all up close. But for some reason, everyone seems to think I'm some legendary hero who solved massive crises in the past, watching over the next generation like a noble predecessor. The truth is, I've never resolved any world-shaking incidents—not even once. This is the story of a reincarnated man who became the manager of a card shop in a world where card games take precedence over everything else. Despite having no great achievements to his name, everyone around him assumes he must have been a hero who once saved the world. (Source: Kadokawa, translated)