Nikon is considering making a Full Frame Z fc version!
Phototrend interviewed Keiji Oishi, head of the UX Planning department within the Imaging division of Nikon Corp. He said this:
As soon as we launched the Z fc, a lot of people were clamoring for an equivalent with a full-frame sensor. Of course, we can’t go into details about upcoming products, but we hear these requests and we think about the type of product that could fully meet them.
I believe this would be a great camera and sell really well!