Yes; technically you are still underway when hove-to. Sails are up and the boat is not tied to the bottom so you are under sail and underway.
The best thing to do if you have adequate room is to heave-to on starboard tack (windward side is the starboard side). Since you are on starboard you are privileged over any other sailboat that is on port tack or windward of you; so your only concern for sailboat traffic would be a leeward boat approaching on starboard.
Of course you are still burdened for vessels with restricted maneuverability, commercial fishing vessels, and ship traffic who generally don't change course for small boats.
You still are responsible for keeping an adequate watch; and the only way to do this while I can think of while singlehanded is to set a
Radar with proximity sensing capability/alarm (MARPA) to do a sweep every 5 minutes or so to check the area for approaching boats or ships.