The Heroic Tale of a Failed Magic Sword User is a Manga/Manhwa/Manhua in english language, manga series, english chapters have been translated and you can read them here. You are reading chapters on www.mgeko.cc fastest updating comic site. The Summary is

[Cut through adversity and defy the world with your sword!] Hollow is a boy who was born in a world where magic was at its peak, and under the heroic bloodline ‘Vermillia’. After birth, he was expected to hold immense magic reserves, but it turns out he was diagnosed with a condition called ‘Magic Oversensitivity’ which disabled his ability to use magic. Shortly after, Hollow’s disappointed father gave up on him and burnt a crest onto his hand labeling him as a useless human being… Right when all hope is lost, in Hollow’s search for what he could truly accomplish, he stumbled upon a dungeon. And within that dungeon, Hollow had found a sealed magic sword “Kasumi”, not knowing she would change his life. “I’ll become the strongest Swordsman in a magic-ruled world!” In exchange for magic, Hollow would slowly learn that he had instead gained the ability to cut through every conceivable form of magic?!