One thing we found out to our detriment is that everybody has to be there for the start of the campaign. We had one player who could only join 2 hours later, and the game didn't allow him to make his own character. He could take over one of the NPCs, but that was it. There also isn't much in the game that would allow players to communicate. We basically communicated on a completely separate Discord server. That was very necessary, because the game allows players to go in completely different directions, which has a potential for a huge mess.

Fundamentally, if you choose to play multiplayer, you simply play through exactly the same campaign as in single player. Including going through exactly the same thousands of lines of dialogue. Any player in the group can start a conversation, and then the others either have to just wait it out, or they can watch the dialogue. They can "vote" for a dialogue option, and the system shows who opted for which, but only the person initiating the dialogue can actually choose or make rolls. With all of us having already tried the game solo, going through the dialogues again, or waiting for somebody in the group to do so, wasn't much fun.

The turn-based combat as a group was fun, but there really wasn't enough of it. Also there is this strange system of shared initiative, where if different players have the same or similar initiative roll, they act simultaneously. Certainly done to speed up things, but of course we had some situations where two players targeted the same enemy, and the first killed it, while the second player's attack then failed and he lost his turn.

Where the multiplayer game really needs work is in communication between players. What decisions in the game need to be made together, and which ones are individual? For example, curiously, if any player presses the short rest button, there is directly a short rest for everybody, no approval from the others needed. But for a long rest there is a system where everybody needs to approve before it happens.

If you have a group of good friends, it is possible to play Baldur's Gate 3 together. It would be absolutely unplayable with a bunch of strangers. And even with friends it feels more like a shared single player experience than really a multiplayer game.