Try to add the following code snippet to the Custom CSS area in Theme Settings.

body .product-grid-item .hover-img {
   display: -webkit-box;
   display: -ms-flexbox;
   display: flex;
}

.product-grid-item.state-hover .product-element-top .hover-img {
    opacity: 1;
    transform: scale(1.09);
    -webkit-transform: scale(1.09);
}

Regards