Question about Nikon Z6 II

No, because it is not an SLR. There is a self-timer (or remote shutter release or via the Nikon SnapBridge app) to release the shutter smoothly from a tripod, for example.

The Z6 II is not an SLR camera, so there is no mirror that can be flipped up before the shutter is released. It doesn't need one, no mirror also means no camera shake when flipped up