Reborn To Master The Blade From Hero-King To Extraordinary Squire (Manga) Vol 01

Hero-King Inglis's last wish is to live again as a warrior. But when he awakens, he realizes he's been reborn as a girl to a noble family! When she's rejected from the knighthood, she sets out to be the most extraordinary squire there ever was. Yen Press
(W) Hayaken (A) Moto Kuromura