Clicking on the hover Slider, the new picture that i upload appear on different sizes,
Look the example on the last color of “Bianca” and the Red color on “Mochila Laira”
I think that the problem is on the automatic miniatures, but
How can i fix that?
Very likely at the start you have used default woocommerce image settings (WooCommerce > Settings > Products > Display) – 300×300+hard crop. Then you have changed image settings but did not regenerate thumbnails.
Go to Plugins > Install and activate Regenerate thumbnails plugin, go to Tools > Regenerate thumbnails > regenerate all.