The last time we saw Ghost of Tsushima was in E3 2018, and the very short teaser above unfortunately doesn't tell us much about the game's progress.
The good news is that in 3 days, it should appear at the Game Awards according to Geoff Keighley, the master of ceremonie.
As a reminder, Ghost of Tsushima has no release date yest, and it's only scheduled for PS4 at the moment.