@ugdpy I don't know how it works for other platforms, but on PS5 I create a PSN party for voicechat, and from there my friends can join my game, and if there's room they will be put in the same squad, or team if my squad is full. Only in case my team is full and there's room in the enemy team they will be put there. After the match is over and a new matchmaking starts we will all 4 be put in the same squad.
That being said, I don't know what currently happens if there's more than 4 in the PSN party as there's only are 4 of us.