Until now, the game had been unavailable in Japan.
It may be hard for many to believe this, but Gears of War 4 was never launched in Japan- the game’s violence apparently led the local rating board to conclude that the game simply could not be released in the state that it was, not without significant cuts (for context, previous Gears of War games had launched with heavy censorship in the country).
However, without any warning, Xbox’s Japan channel has shared a new video for Gears of War 4, very carefully noting that the game has been rated CERO Z- CERO Z is the highest possible age rating that a game can get in Japan, and it is legally enforced. In terms of market implications, it is somewhere between an ESRB M and ESRB AO- most publishers actually try to avoid the rating, but it appears as though Microsoft may have accepted it to simply get the game to release in Japan at all.
As of right now, there has been no official confirmation of the game’s release (and therefore, certainly not a release date or even release window) in the Land of the Rising Sun- but things are looking better now than they did before. We’ll keep you posted.