International musical collaboration with Audacity as medium is indeed feasible, in principle.
Two years ago (I think, anyway), I met an amazing German ukulele player, online, performing classical music on his instrument. Technically it’s well-executed - and really beautiful too.
I asked him if we could do something together - and since we both like Dowland songs very much, the plan was to cooperate on one of those. However, differences in our musical backgrounds (mine jazz; his classical) - and, hence, in respective approaches to notation - soon put paid to that resolution: our Dowland song never even coming off the ground.
The way we communicated musically was via Box.com. My temporary ukulele partner recorded on a small, portable Zoom recorder, with the aid of a sophisticated microphone. Next, a .wav audio file made out of this would then be added to his Box account, after which he’d email the link to that recording to me.This, subsequently, went into Audacity, at my end, in order to add a second voice (tenor guitar, usually). Of that outcome, too, a .wav audio file would be made as well and returned in the same manner.
This went very well for a while. So, entering into similar cooperation again - this time with (a) musician(s) versed in Swing/swing (let’s say Mainstream Jazz in general) - certainly appeals to me, based on the experience aforementioned. Perhaps even a brand new forum could be set up under the general Audacity forum umbrella: an Audacity musician pool facilitating instrumentalists and singers from all over the world to work together in this manner a fantastic addition, if you ask me!