I exited Schengen out of Dusseldorf today. There was no one there when I got to the border checks. No machines but the booths were manned. There was also a set of egates for those with EU passports.
Since I have EasyPass, I can use the egates. And I did. No sweat. Got through easy.
It then said see an officer. And a booth was right there.
I handed him my passport, he looked through it and asked where was my entrance stamp.
I told him I entered in Vienna, had my fingerprints and photo taken, but they don't give stamps.
He fiddled with his computer, looked stumped and then asked if I had any proof of when I entered Schengen. I showed him my eticket and that was fine.
He told me that Germany still wants stamps but they realize some countries, like Austria and France, no longer stamp. He then had me place my fingerprints on the machine and took my picture.
He said to wait there. He took my passport to one of the regular booths where I got an exit stamp.
He was nice about everything and said that Germany still wants stamps but realizes some countries have stopped.
So, if you exit Schengen from Germany, but enter from another country, have some proof of your entrance into Schengen such as an eticket or some other confirmation..
He said they would probably keep stamping until ETIAS.