We should soon be getting an updated Nikkor Z mirrorless lens roadmap – the current version has not been updated at least since January and it shows only 3 specific lenses for 2020 with 4 empty slots.
On their dedicated mirrorless lens site, Nikon USA acts as the Z-Noct-Nikkor 58mm f/0.95 lens is already officially announced – it’s present in the Z lens group picture and it’s hyperlinked in the Nikkon Z roadmap similar to all already available lenses (see above screenshot) but it is still marked as “coming soon”:
The Nikkor Z Noct 58mm f/0.95 mirrorless lens is rumored to be released in September/October and the price could be as high as $8,000.