.custom-figure {
    position: relative;
}

    .custom-figure img.custom-image-hover {
        position: absolute;
        top: 0;
        right: 0;
        left: 0;
        bottom: 0;
        object-fit: cover;
        opacity: 0;
        transition: opacity .2s;
        height: 100%;
    }

    .custom-figure:hover img.custom-image-hover {
        opacity: 1;
    }