Perhaps my friends and I are literally the only group of 4 people on Stadia try to play co-op (or I would expect to see more about this), but joining a co-op game on Stadia is virtually impossible. I'm part of a party who played Divinity every Sunday morning and since we just finished out playthrough we've tried to do the same thing with BG3 on Stadia and we burn multiple hours just trying to play together. I'll call us PC-C, PC-A, CC-M and CC-H where the first two letters are the platform we're on (Desktop PC or Chromecast) and the other letter is just an initial to help me keep things straight.
Play attempt 1 (10/8): Honestly don't remember specifics but PC-C tried to host the game several times, we were creating our characters and CC-H hit a bug where they went to their love interest early and couldn't get back to finish creating their character. After that, no matter how many attempts, no one could join PC-C after trying to start from scratch. We eventually wound up getting everyone's into a game hosted by CC-M. We got through character creation and played some on the ship.
Play attempt 2 (10/11): CC-M tried to invite us after loading our saved game, every attempt gave everyone an error message claiming there were no characters available to be assigned to them. CC-M found the session management screen and couldn't find any way to free up characters using the controller, so we decided there must not be good controller support so it might be a bad idea for someone on Chromecast to own our saved game, so we flushed that down the toilet and decided to start from scratch with PC-C hosting again. Tried inviting everyone, can't remember specifics again, but one person's game crashed trying to join and then that person was never able to re-join us at character creation. Despite completely killing the game, that person was never able to rejoin. We tried hosting with one of the CC hosts starting a new game and invite everyone, somewhere along the way we came to the conclusion that once someone left the game, it was impossible for them to re-invite someone. Remembering our lesson about wanting to make sure a PC host the game, we put all our eggs in the PC-A basket and were able to successfully get everyone in and played for a good 3 hours.
Play attempt 3 (10/18): PC-A Loaded the game, invited us all, CC-M and CC-H were able to join, PC-C just got the same "Joining Failed: Something happened on our end. Try again" like 20 times, Literally no attempt at even a loading screen, immediate failure. Taking note of the 2 characters who were able to join on CC, C moved from PC to CC, same error, not even a loading screen. We decided to kill the game in Stadia. PC-C and CC-H joined successfully, CC-M got an error saying there were no characters free. Couldn't find any way to "free" up a character. Killed the game, started over, same exact experience. Concluded there was something about the 4th player joining. Killed everything, decided to invite one person at a time. PC-A loaded the save, invited _just_ CC-M, he got a loading screen! He got into the game successfully... Someone else's game... He was in a game with strangers. He killed that, we spent the next 90 minutes taking turns being invited one person at a time, into the game hosted by PC-A to no avail, in that time we had 2 instances where anyone was able to successfully connect, but never all of us. We decided to try loading the game saved on CC-M, didn't get anyone in successfully. Then we decided to try having PC-C start a new game (create on multiplayer), invited everyone, CC-M's invite crashed, both CC-H and PC-A wound up loading into strangers games... We're giving up
Are we the only 4 people playing on Stadia with an actual 4-person party? Is Larian just concentrating on Steam and leaving us high and dry? I know the first 2 days the Multiplayer menu couldn't even load on Stadia, which implies they're not trying _super_ hard since that seems like it would jump out to QA pretty quick. If Steam is the priority, I can live with that, but I'd love some communication of that point so that we don't waste 2 hours every Sunday trying to load a version no one is paying any attention to...