Geek alert! A Canon vs Sony vs Fuji vs Nikon shootout on Eye AF performance.
Here is a 22 minutes video where Hidema Nakajima compares the Eye AF of various mirrorless cameras. To be more precise, he compares the Eye AF performance while shooting 4K video. The compared cameras are the Canon EOS R, Nikon Z 6, Sony a9, and Fujifilm X-T3.