Habe nun etwas gefunden im Web anhand Unique_key. Scheint auch zu funktionieren. Der code ist von https://businessbloomer.com
/**
* @snippet Display Separate Cart Items for Product Quantity > 1 | WooCommerce
* @how-to Watch tutorial @ https://businessbloomer.com/?p=19055
* @sourcecode https://businessbloomer.com/?p=72541
* @author Rodolfo Melogli
* @testedwith WooCommerce 3.0.7
*/
// -------------------
// 1. Split product quantities into multiple cart items
function bbloomer_split_product_individual_cart_items( $cart_item_data, $product_id ){
$unique_cart_item_key = uniqid();
$cart_item_data['unique_key'] = $unique_cart_item_key;
return $cart_item_data;
}
add_filter( 'woocommerce_add_cart_item_data','bbloomer_split_product_individual_cart_items', 10, 2 );
// -------------------
// 2. Force add to cart quantity to 1 and disable +- quantity input
add_filter( 'woocommerce_is_sold_individually', '__return_true' );