The GOG Galaxy client was always intended to be a launcher where you could organise and browse all your PC games in one place. Right now it can manage most PC games via various official and community-created integrations but a new beta takes things a step further - allowing the purchasing of games from other online PC stores via the app.
The beta of the GOG Galaxy 2.0 app facilitating 3rd party store purchases, available by invite only for now, allows users to browse and purchase a number of Epic Games Store former exclusive titles such as; The Outer Worlds, Mechwarrior 5: Mercenaries, and Mortal Shell. As the beta progresses GOG will be inviting more folk to join, so if you are interested you are encouraged to sign up at gogalaxy.com.
In addition to the convenience offered to GOG Galaxy 2.0 users, any games available via the app will be covered by GOG's more generous than average refund policy. Yes, GOG allows purchasers of its own distributed and Epic Games Store integrated titles 30 days in which to request refunds (with no restrictions on game play time within that period). For comparison, the EGS and Steam allow refunds within 14 days on games purchases that haven't been 'played' for over two hours.
Epic bought games via GoG Galaxy will still require the purchasers to have an EGS account. Once bought, you will be able to launch the games through either the GoG Galaxy app or the Epic Launcher.
GOG hints that titles from other stores will start to become available via its Galaxy client too.
In related news the EGS is currently giving away Pikuniku, with ABZU and Rising Storm 2: Vietnam queued up for next week.