Honestly... it's not great. I would not recommend it unless you're playing with somebody who is not put off by constant bugs and general jank.

In terms of bugs, I've had several occasions where one player can no longer open the map - it just starts opening the quest log instead of the map. I've also had a few occasions of the screen just going completely white. Also, I've had a player just become locked in a dialogue with no way of exiting.

For an example of jankiness, one key aspect of the whole game, dialogues, is just completely awful:

1. Both players can begin separate dialogues at the same time, one just gets muted
2. It's impossible to automatically begin a dialogue with two players, one player has to start it, and the other has to "listen" to it as an additional step
3. It's impossible to switch control of dialogues during a dialogue. This is constantly an issue, because sometimes, dialogues are triggered when you walk past some invisible checkpoint. Basically you're forced to always have your high charisma player to walk in front and hope they end up triggering all the dialogues.
4. It's impossible to contribute to dialogues in any way as the "listening" player. Even if you have some aspect to your character that might provide an interesting line, you are just locked out.
5. If both players speak to a character in succession, the exact same dialogue gets repeated. It's jarring and completely breaks immersion.

There's more, but I'm kind of getting more and more annoyed at the game as I write this, so I think I will just stop here, you probably get the picture 😅

I think the co-op is a complete afterthought in this game, and I will probably be replaying it in single player for a hopefully better experience at some point.