The Viltrox AF 28mm f/1.8 lens is now released also for Nikon Z-mount. Pre-orders are already open at B&H Photo (check also the Viltrox Amazon store and Viltrox website):
The Viltrox AF 28mm f/1.8 lens is already available for Sony E-mount (product listing):
Upcoming/rumored Viltrox lenses: 16mm f/1.8 full-frame and 75mm f/1.2 APS-C for Z and E mount
Via NikonRumors