I picked up Destiny 2 when it was offered for free on Battle.net. I have recently transfered my license to Steam, but I've never really played much because my laptop can't run Destiny 2.
Enter Stadia. I've played a lot more of D2 since Stadia's launch. And for whatever reason I've enabled cross save at the beginning, setting my Steam account as my active account. Of course I never went back to that one old Guardian I had created but instead started from the beginning, so it was entirely unnecessary.
On Stadia I own the Collection with both expansions. On Steam I've only owned the base game which now is New Light, I believe. My question is, have I restricted myself to playing New Light by setting Steam as the active account for cross save? Or am I still playing the whole Collection on Stadia even though my Guardians are saved to Steam? How am I able to tell in-game which version of D2 I'm playing? The splash screen says Shadowkeep but it doesn't tell me whether my Guardians are running on the Shadowkeep version or somehow not (because they are linked to Steam).
Is there a way to disable cross save and transfer my Guardians to Stadia once and for all? (I assume not.)
(Edit: According to the Migration screen from Battle.net I should also have Forsaken on Steam, but according to the Cross Save page I don't have it. But this seems to be a different problem.)
Licenses are bound to the platform you're playing on. So if you own Shadowkeep on Stadia and play on Stadia, you'll be able to access all Shadowkeep content and activities. If you do not own Shadowkeep on Steam you wouldn't be able to access Shadowkeep content on Steam. It doesn't matter which characters are active.