UPDATE 3:40 AM: Square-Enix has confirmed that the game is a survival action shooter. In addition to the credits below, Takayuki Yanase (mech designer for Xenoblade Chronicle X, Ghost in the Shell, and Mobile Suit Gundam 00) is also involved.
The original story is as follows:
During Sony's TGS presentation, the publisher and Square Enix revealed a teaser for a new game called Left Alive. The teaser was short and CGI, revealing gunshots peppering an apartment hallway, followed by an explosion that showcased a seemingly post-apocalyptic cityscape.
We didn't see much else except some credits on the project, including news that Yoji Shinkawa, who did environmental and character artwork for both Metal Gear Solid and Zone of Enders, is working on the project as a character designer. Other credits include producer Shinji Hashimoto (Final Fantasy, Kingdom Hearts) and director Toshifumi Nabeshima (Armored Core)
Left Alive will be released sometime in 2018.