Why not have a single chatroom in Duolingo with real-time edit suggestions and real-time translation?
Such a chatroom could have a column for each language supported by Duolingo.
You type in the language you are learning and what you type appears in the appropriate column.
Anyone else (learners or native speakers) could offer edit suggestions in real-time to improve what you typed.
Moreover, anyone else (learners or native speakers) could translate what you typed in real-time so it appears in the other columns. And those translations could have edit suggestions also.