Though no early record of her being known survives in Japan, or Nippon if one insists on being obscure, she was known from the Tokugawa period (1603--1868) on at the very least. Her local name was Futashita-Onna, or Lady Two Tongues, and she was the subject of many woodcuts, some of them unsuitable for the weak-kneed and children of all ages. Despite some wild speculation on part of Western mythologists such as Hearn, it is most likely that her figure and attributes were carried to the Land of the Rising Sun by Portuguese traders before or early during the Tokugawa period of isolation. The differences in her character and the unfamiliar aspects of her legend can be explained by the same isolation and hostility to foreign influences: the differences were the result of a necessary process of naturalization that was the way of all those foreign elements that were not abandoned.
One should remember that in Japan's unique religious mixture of Shintoism and Buddhism Futashita-Onna was merely one of many gods, and most probably regarded more as a "monster" or a "yookai" rather than an actual divinity, though in Japanese folklore no such stigma of negativity attached to yookai as with the Western dragons, hobgoblins and other Satanic beasties.
One intriguing folktale positions Futashita-Onna as the queen of the tanuki, or the Japanese raccoon dogs (Nyctereutes procyonoides viverrinus), thought to be shape-shifters, magicians, and bringers of mischief and occasional good luck. The tale, possibly faintly echoing the Grecian tale of the Golden Apple of Eris, has the Tanuki Queen preparing a great feast, inviting great many attractive maidens from the surrounding countryside, and so mixing the crowd that no-one could know who was a girl invited there, and who a tanuki in exceedingly beautiful female shape. One human girl, however, reputed to be the prettiest of all of them, refused the Queen's call. The Tanuki Queen was angered, spat out the octopus dumpling she had in her mouth, and the girl-tanuki all sprouted octopodean tentacles and horribly molested the attending maidens. (This tale has been adapted, with some liberties, in the Taboo XXX Fairytale series of animated "anime" folktales from around the world.)
Tsukioka Yoshitoshi, best known for his exquisite woodblock print "Rainy Day Tanuki" (1881), apparently also drew a print called "Queen Tanuki and the Fisherman's Wife"; but no copies of that work survive.