As of the 26th of November 2021, The first volume of the Sakuna: Of Rice and Ruin manga (天穂のサクナヒメ 戦だたらの神々, translated, Sakuna: Of Rice and Ruin – Gods of Ikusadatara) has been released online for free on Hero's Web Viewer[1]; the manga begins an entirely new story in the Lofty Realm, entirely different from the game.
According to a fan translation:
Gods of Ikusadatara will tell a different story from the original game. Sakuna discovers a mysterious berry while hunting for food ingredients. When Sakuna opens the berry, she finds twin babies that will drastically change her daily life.
While serialised, update frequency is unknown; the manga was announced on the 1st of November 2021 as part of Hero's Web's 10th anniversary[2].