Liang Bu Yi

His Majesty comes close; he's so handsome that the flushed queen pushes him reflexively and falls with him into a pool of water. Then they swap their bodies. The way to swap back is unknown. The most important thing is that the emperor is quite angry now!! Since they can't return to normal, the emperor has to deal with his mean imperial concubines that he doesn't even know, and the queen has to mediate between high-ranking ministries...

(Source: Webnovel, edited)