Everything sold out.
A common theme these days. Looks interesting
https://wiki.zynthian.org/index.php?title=Beginners_Headless...
ZynthianOS can be configured with external MIDI controllers for the menus, etc. That might be a bit of work, but its definitely worth the effort, because ZynthianOS is just amaze-balls. NORNS too, its just astonishing the power in these little distros.
As well as the original Zynthian, I also have Zynthian running on one of these:
https://www.audiophonics.fr/en/open-source-streamers/rasptou...
.. with a touch-pad, and its just such a tidy, neat system. I look forward to this particular flavour of machine becoming much more prevalent in the MI world ..
You can. The results are not great. A sound card is required.
I have a Pisound
https://zynthian.org
Monome NORNS:
https://monome.org/docs/norns/shield/
Both of these Linux vendors have created what you describe - definitely worth checking out if you are a performing musician. These machines transform into viable, usable instruments - you don't have to do much Linux hacking, you can just plug in and play, like any other electronic musical instrument, and some of the stuff in the NORNS community is amazing for live performance (actually most of it is):
https://norns.community
Both systems will let you play with MOD DUO, which is a plug and play effects system that kicks serious ass:
https://moddevices.com/devices/dwarf/
Other than that - definitely check out Ubuntu Studio, as others have mentioned. I've been running it for a decade as a production DAW in my studio and it really kicks ass... you will be astonished at what is included, out of the box ..