Does anyone have an experience with the non-Galaxy version from GOG? I have the suspicion that Stellaris is no entirely DRM free when using the offline installers.

are you running it from the paradox launcher?

The Singleplayer part is drm free. For the Multiplayer you need to log in to a Paradox Account.

are dlcs drm-free too?

On steam, its that - game itself is drm-free aswell. BUT you need to launch it with online connection and steam running on background at least once, to make dlcs work (then game creates some encrypted cookie-like file in its save folder). Otherway game wont see them.
Wonder if thats the case there too

No need for any of that with the GOG version of the DLC.

No Paradox account required (I have one but never logged into it from the game), no Internet access that I know of (I already ran the game with DLC on an offline computer), no Galaxy (never used it, never will).