So it is a program running in the program from Archipelago that can connect multiple randomizers together. You can have a friend playing a different randomizer somewhere else and you can send them item for their game and vise versa. Or you can run an a-synch on your own by doing everything you can in one game, and then swapping to another.
They have a list of compatible randos on their website, and I’d be willing to answer any other questions you have