So basically (if it's possible) like players could choose what and who they play with like ps4 with ps4 or ps4 with pc or xbox with switch etc
They meant that for example a mobile player choose to play with ps4 players, or a pc player to play with Xbox ones.Not sure if I am understanding this correctly, but you can invite someone to a party so that you can play with them, regardless of what platform they are on. Do /p invite (player's username) and then they have to accept.
Not something they should add, as @SwedishMelon said, play with different platforms through a partySo basically (if it's possible) like players could choose what and who they play with like ps4 with ps4 or ps4 with pc or xbox with switch etc