Take a look at the list of compatible lenses for Nikon and Canon Fullframe Mirrorless camera. We are one of the first website to talk about the compatibility of Nikon Z7 / Nikon Z6 Mirrorless cameras with third party lenses. Now its time for list of official lenses coming out from Sigma.
Compatible Nikon and Canon Fullframe Mirrorless Lenses
Canon List of compatible lenses
Nikon List of compatible lenses
Sigma 150-500 USM was found to be non compatible. AF does not work. But works when both camera and Lens are put into Manual Focus mode.
Also tried 600mm range Zooms of Tamron. While those of G1 allow shutter without AF, with G2 big lenses, the Z6 shows ERR… message.