In this novel, the main world reminds me of another novel called The Regressed Mercenary's Machinations. I'm not sure if it's the same universe or the same world, but it feels very similar to me. If anyone knows what the original world is or if it's based on another novel, let me know.
"It seems illogical to move the Demon Slayer headquarters to the Swordsmith Village. If by chance Muzan finds them again, he would be destroying two crucial bases at once—the swordsmiths and Ubuyashiki’s headquarters. If they are unable to defend themselves, that could mean the end of the Demon Slayer Corps."