I've never had a sorority, so I can only go based on what I would do in your situation, and why. I have, however, moved my male from his bowl to a tank with some shrimp and snails in it. But here are my 2 cents anyways. lmao.
I would treat it like you had just brought them home for the first time and acclimate them each individually, then, when it comes time to release them all, release them one at a time, from the most submissive to the most aggressive, and maybe give them a minute or two to establish a territory before releasing each new girl. The reason that I would do it this way is because of a few different things. First and foremost, they are moving to a new environment which is foreign to them, and therefore, they may establish a new pecking order. Secondly, moving into a new environment can be stressful, so giving them time to properly acclimate will reduce that stress. Finally, while the tank is the same temperature as their current one, and may even have the same water parameters, the bacteria in the new tank might not be the same/at the same levels and that of the old tank, so, again, acclimating will give them a change to adjust.
That's how I would do it. I don't know if that's the proper way or if there is a more experienced sorority owner who has a better way, but that is mine. :)