Dorei kara no Kitai to Hyouka no sei de Sakushu dekinai no daga

A reincarnated boy, Allen, gets granted by a goddess the cheat skill, [Restoration]. Even though he can heal all and any injuries and illnesses, there aren't a lot of places where he can use that skill to the fullest, so he planned to "regenerate" the slaves he bought and lead a slow-paced life. But the healed slaves' cheats turned out so out of the ordinary that the crops they tend to and their living conditions turned for the better in a blink of an eye.