Make images black and white in Elementor Builder

Add css class to your image or slider element: bw-color

add the following css to your theme customizer custom css section or your theme css files:

.bw-color img {
     /* filter: url(filters.svg#grayscale); Firefox 3.5+ /       filter: gray; / IE5+ /       -webkit-filter: grayscale(1); / Webkit Nightlies & Chrome Canary */
       -webkit-transition: all .4s ease-in-out;  
     }
 .bw-color img:hover {
     filter: none;
       -webkit-filter: grayscale(0);
       -webkit-transform: scale(1.04);
     }