The Heroic Tale of Shura Young Girl: A Mercenary Who was Said to be Half-Baked is Reincarnated as a Young Girl and Rises to Success is a Manga/Manhwa/Manhua in english language, Action series, english chapters have been translated and you can read them here. You are reading chapters on the fastest updating comic site. The Summary is

"If I had a second life, wouldn't I be able to aim to become a 'hero' again?" Solfort Enuma is a veteran soldier who has spent over sixty years training to become a [Hero]. He is an ordinary man with no talent, but he never gave up and continued to pursue his dream. One day, Solfort faced off against the [Hero] he had always admired, but his sword failed to land a single blow and he met an unrewarding end... or so he thought, but when he woke up, he found himself reincarnated as a little girl--!?