Hello,
is there any way, when only need to see color variation gallery, customers only need to click color button?
By default, WooCommerce requires all the attributes to be selected to show another variation image or variation gallery. There is no way to show the gallery by the click of the color only. YOu may set the default form value to show the gallery once the user visits the product http://i.prntscr.com/BlFqGPo2TnKqJirAAQDitw.png
Regards