Hello,

1. Enable “Use images from product variations” in the Theme Settings > Shop > Variable products;
2. Upload the image to the product variation in the product page > Variation (in the product date block) > select the appropriate variant and set the main image.
3. Remove the color from the attribute item in Product > Attributes > Select the attribute > Configure items > Select the attribute item, set the image, and remove the color.

If you have any questions please feel free to contact us.

Best Regards