Remake Relife: 30-sai ni Naru to Jiyuu ni Seibetsu to Karada wo Tsukurinaoseru Sekai no Hanashi

While working on a figure, the sculptor Tsukasa Tominaga longed for the small hands of a woman that could help improve his progress. Because he turned 30, Tsukasa then receives a "Body Remake Application" notification... It seems that recent research has allowed for humans to freely remake their bodies after the age of 30. Tsukasa gives it a shot and remakes his entire body to that of a woman's—but after going home—he finds out that his wife Subaru (30) underwent the same procedure and is now a man?! With their minds unchanged and their bodies reversed, the couple begins their second life together!!

(Source: Kadokawa, translated)