Nikon has released eye AF firmware updates for Nikon Z6 and Z7.  Here is the video comparison of Sony a7 III Vs. Nikon Z6 Vs. Canon EOS R on eye AF. From the result, we can see Sony a7 III’s eye AF is still much better than Nikon Z6 and Canon EOS R.

Eye AF Comparison: Sony a7 III Vs. Nikon Z6 Vs. Canon EOS R