I'm not aware of any, but would be interested as well. I used to contribute to Wikinews - and did some translations there of articles to and from english, but that typically was by myself, not collaboratively.
You say your interest is in translating linguistic academic articles - I assume that you're thinking of open access, that is freely shareable and changeable, articles then (since otherwise distribution of the translation would depend on permission of the journals publisher, which I'd think is tedious to get)?
If that's the case I guess you could give a shot at asking the people at Glossa whether they have any interest, or might be able to give you a hand in some way. I've not had any personal experience, but from how they came about founding the journal, they certainly seem like people of action ! (They collectively stepped down from a prestigious non open-access Journal to found it).
Good luck, and best give a shout here if you run into anything interesting!