Hello,
If you upload the featured image with size 650×650 then use 650×650 image for the variations. If you upload featured image 650×500 then use 650×500 image for the variations, that’s all. And there won’t be any problem of scalled images https://gyazo.com/224e6e7d6217c324fa24c584d2f12143
Product gallery image jumps up on hover https://gyazo.com/58847cb15a140601eec6c28087cdff69 to highlight the image you plan to click. If you don’t like this effect add the following custom
.thumbnails-list .slick-slide:hover a, .thumbnails-list .swiper-slide:hover a, .thumbnails-list .active-thumbnail a {
transform: translateY(0);
}
Regards