I have a 4 HP hot ********* compressor that's in a crawl space back of the garage wall, roughly 6' feet above the garage floor. All of the compressor functions are brought out to a panel on this wall, including the air drain, so most operations can be done from this side, other than oil check / change, air filter service, and belt service. The elevated platform the compressor sits on is about 4" above the top of this panel.
All that I needed for this was a 72" x 3/8" hose whip, and a feed-thru hex reducer to join the hose end and the tank's standard drain petcock - you can see the latter two items in the image above. The reducer uses a washer and nut on the outside threads in the back of the panel to mount it, rather than a plumbing fitting.
And I did make sure that the hose was always descending, so as not to trap any water.
It does mean that hose whip is always at full tank pressure, but the one I got is a decent brand and rated 300 PSI. When I need to replace it, I replace it. And I always drain the system down at the end of the day anyway.
And yes, this just blows the water out onto the floor. No big deal, there's not a lot coming out.