REINCARNATED. THE SWORD SAINT WHO BECAME A SHORTY PRINCE TO HIS FORMER DISCIPLES ~ I DON'T WANT MY FORMER DISCIPLES TO FIND OUT 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 www.mgeko.cc fastest updating comic site. The Summary is

Sword Saint Brise saved the country with his unique swordsmanship.At the end of his magnificent life, he is reincarnated as the country's youngest prince, still retaining his memories.He seeks freedom again and aspires to enter the elementary school of knight school.Even though he is an invincible swordsman, he unexpectedly fails! I came to get you.He looks like a child, but inside he's an invincible former swordsman.In his reincarnation, he is picked up by his former disciple!?