This article says the deck struggles to run baldur’s gate 3, but it runs fine for me other than eating through the battery (to be expected) so I’m a little doubtful that Alan Wake doesn’t work that well
Baldur's Gate 3 suffers on the steam deck due to CPU limitations. It struggles with running all the simulation behind the scenes, especially in large open areas.
Not sure if Alan Wake has the same CPU needs. I'd suspect the graphics themselves can be scaled down.