Out of stock

function kt_display_out_of_stock_loop_woocommerce() {
    global $product;
    if ( ! $product->is_in_stock() ) {
        echo '<span class="soldout">Out of Stock</span>';
    }
}

add_action( 'woocommerce_before_shop_loop_item_title', 'kt_display_out_of_stock_loop_woocommerce' );