I've basically been checked out mentally for a while, with regards to gaming news, so I haven't really been cognizant of what gets released in 2019.
That said, while I am not sure if it counts and while I am not sure the first chapter will even be out in 2019, my answer has to be the recently revealed Ciconia no naku koro ni, the next entry in the 'When They Cry' series of visual novels by 07th Expansion:
I would also have said Doom Eternal and Rage 2, but I am not willing to contend with Bethesda's client/store tomfoolery, and so I'll have to wait for that to get released somewhere sane down the line.