it wont work for me when i am using an adapted manual lens
additionally, i noticed that the sensor has a lot of play! shake the camera and you can even hear it rattle!
The Zf has a new implementation of in-camera VR which doesn't have the lock feature which previous Nikon implementations had. So the motors are the only thing keeping the sensor still. When the camera is off, the sensor can move about. I believe the reason they did this was because of the small size of the camera.
I like the sensor lock actually as it gives me confidence the sensor is exactly centered to the same place every time (I hope) and won't move by external forces applied to the camera.
Some videographers say that in cameras that have non-locking IBIS the sensor can move a little when the camera is moved during takes and they claim the sensor's residual responses to camera movement affects the image somehow in a way that they don't like. However, I am not sure if this is a real or imagined effect.
Anyway the Zf is as it is, no VR lock in the body.