sammies
If you are using the latest version of Hypermarket, go to Appearance > Customize > Product Archives. There you can change the number of WooCommerce products displayed per page.
Also, the following snippet might enable you to customize this number upon your needs.
function prefix_products_per_page( $per_page ) {
$per_page = 9999999;
return intval( $per_page );
}
add_filter( 'hypermarket_products_per_page', 'prefix_products_per_page', 20, 1 );