Yes. We have designed PlayoutONE with 4 on screen players and each player can output to any audio device on your machine. There is also a 5th device which is for editing and previewing audio this can go through it’s own device as well. You may want everything to go through just one device – [...]

Not at the moment. PlayoutONE is for Windows and is supported only by Windows 10.

Yes, however, "In space no one can hear your stream"