(Source)
Not exactly the freshest or most exciting news but I guess a thread couldn't hurt in the run up to E3.
The game has been rated M, which I'm told is around the equivalent of a 12+/15 or T elsewhere. The game has been rated for very mild impact with sex/sexual references, mild impact for themes and language, and moderate impact for violence.
In case you missed it; Shenmue III will also be playable for press at E3 in two weeks time. Sessions are apparently fully booked, so there should be a healthy batch of impressions to read, alongside whatever new media is provided for public consumption. In February and March this year, there were also hands-off demos for press that resulted in a series of previews that included being the cover story for EDGE. You can read them here: (EDGE, VG 24/7, IGN, Gameblog, RPGsite)
Shenmue III releases on the 27th of August 2019 on PS4 and PC.