convert *.png -evaluate-sequence mean MEAN.png

convert *.png -alpha off -evaluate-sequence mean MEAN.png

convert *.png -evaluate-sequence mean
( -clone 0 -alpha off )
( -clone 0 -alpha extract )
-delete 0 +swap -compose divide -composite result.png

compare -metric rmse result.png mean_photoshop.png null:
125.167 (0.00190993)

convert xc:"rgba(255,0,0,1)" xc:"rgba(0,0,0,1)" xc:"rgba(0,0,0,0)" -depth 8 -evaluate-sequence mean txt:

# ImageMagick pixel enumeration: 1,1,65535,srgba
0,0: (21845,0,0,43690)  #550000AA  srgba(85,0,0,0.666667)

convert logo: -transparent white logot.png

convert logot.png logot.png logot.png -alpha off -evaluate-sequence mean result.png

magick logot.png logot.png logot.png -alpha off -evaluate-sequence mean result.png

convert logot.png logot.png logot.png -channel rgb -evaluate-sequence mean -alpha off result.png