One of the most frustrating things about Baldur's Gate 3 is getting to the end of a conversation, only to realise later that having a specific companion in your party would have completely changed the course of the game. Worse yet, the idea that you might be missing important plot points for your companions due to their absence.
Uploaded to Nexus Mods by Shagone, the mod "Allows all allies, whether they are party members or not, to participate and react to the player's dialogues, regardless of distance or the party size."
Not only is it toggleable per character—in case you decide there are certain characters you don't want to witness certain events—it works even when you're playing as another character.
"When a character with the Grouped Dialogue status starts a dialogue, all available allies will automatically participate in it and react whether they are party members or not."
Sure the idea of a companion weighing into a conversation from miles across the map is a little immersion breaking, but it does mean you won't miss out on parts of the game you might otherwise have overlooked.
As it says in the description, Norbyte's Script Extender is necessary to get it working, but it's nice to know that the mod doesn't actually change any game files and should be compatible with other known mods.
As of now, the Everyone in Dialogue mod has a few bugs, such as "When you go to bed with the passive enabled, origin characters do not sleep," and "Occasionally, the indicators that a character wants to talk to you at camp are not visible." Helpfully though the description gives some advice to "Check regularly if someone wants to talk to you, particularly Gale."
The modder is also keeping people up to date with vague percentages as to how close each bug is to having a fix, which if you ask me is something game developers should adopt more often, so we know stuff is actually being worked on.