Hello,
Mobile devices do not have hover state as the desktop version, do you want to show the slider arrows always on the product image?
Then add the following code to child theme style.css and clear CDN cache
@media only screen and (max-width: 768px){
.st-content .sm-arrow, .st-content .product-slider .bx-wrapper .bx-controls-direction a {
display: block!important;
}
}
Regards