I was trying to remove the movement from a Hugo Boss watch with a twist setting stem. The movement is a Miyota 1M12 (helps to be near-sighted sometimes) and while other have asked, I could find no explanation for how to remove the stem.
Turns out, if you look reeeeealy close, you might get lucky and see a tiny arrow pointing to a tiny hole. You must push in this hole (with the stem fully depressed) then pull on the stem and it comes right out.
Visual Aides – red arrow points to the stem release hole.
Close-up of the hole
Make sure the crown is pressed in, then use a pin to push down in the hole, and the stem should just be loose. Don’t push too hard, and don’t hold me responsible if you break your watch!