There are certainly groups and parts of German and Austrian society where it would appear the monarchy is alive and well. They are not exactly clandestine, but rather private clubs and organisations where shameless approval and endorsement of the theory that constitutional monarchy would be an asset and positive influence in both countries. They aren't political parties or agitators, but rather gatherings of like-minded people.
I once attended one such gathering in Vienna where, despite the constitutional abolition of titles of nobility, those nobles present were addressed by their appropriate pre-republican courtesy titles.
These views are in some cases, too sensitive for publication in mainstream media, as they also appeal to various forms of extremism. But there are certainly German and Austrian monarchists who retain a quiet hope that they may one day see a restoration of one kind or another.
May she defend our laws, and ever give us cause, to sing with heart and voice, God save the Queen.