Here is a round-up of hands-on reviews and previews of the brand new Canon RF…
High Resolution Mirrorless Comparison (Canon EOS R5, Sony a7R IV, Nikon Z7 II, Panasonic S1R)
Here is a mirrorless comparison with high resolution cameras. Canon vs Sony vs Nikon vs Panasonic.
DPReview compared the Canon EOS R5, Sony a7R IV, Nikon Z7 II and Panasonic S1R, all high resolution mirrorless cameras.