No, Alan Wake 2 won't be on Steam due to its exclusivity with Epic Games Store, funded by Epic Games. The possibility of a future Steam release remains uncertain.
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New Alan Wake 2 The Dark Place Trailer Revealed At Gamescom Opening Night Live
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Remedy: Alan Wake 2 M Rating Liberating, Won't Compromise on the Horror
Alan Wake II Will Run at Native 1080p, High Settings, No Ray Tracing Only for Around 7% of All PC Players
23% of PC gamers probably can't play Alan Wake 2. Here's why
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Alan Wake 2 Announced as Epic Games Store Exclusive on PC