We've known for a few months that Nikon has been working on the eye AF function, but a few days ago this function became widely available thanks to the firmware update to 2.0.
The function works both in the case of AF-S measurement and AF-C measurement. In the case of detecting eyes of many people, one can use the multi-function selector or additional selector and choose the eye on which the focus should be adjusted.
What's more, Nikon has increased the sensitivity of the whole AF system to the value of -2 EV in Z 7, and to the value of -3,5 EV in Z 6.
Another novelty is individual exposition measurement for full frame, conducted in a quick continuous shooting series.
Online materials which are available up to this point present very positive opinions about eye AF in the AF-S mode. Unfortunately, this function works much worse in the case of the autofocus in the AF-C mode. Still, Nikon deserves recognition since it managed to implement this function to the first series of mirrorless cameras (it seems, a bit under the pressure of users) although it wasn't its plan during the premieres of Z 6 and Z 7.
You can download firmware v2.0 for the Z6 and Z7, head on over to the Nikon Download Center.