Rename Item Name from Cart Page

You can use following woo-commerce filter to rename or update item name from cart page.

www.yourdomain.com/cart

add_filter( 'woocommerce_cart_item_name', 'change_orders_items_names', 10, 2 );
function change_orders_items_names( $item_name,  $cart_item,  $cart_item_key ) {
   // Do you changes to $item_name here
   $item_name="New Item Name";
    echo $item_name;
}

Rename Item Name from Order Completed Page

You can use following woo-commerce filter to rename or update item name from order completed page.

add_filter( 'woocommerce_order_item_name', 'update_order_item_name_custom', 20, 3 );
function update_order_item_name_custom( $item_name, $item, $is_visible ) {
    if( is_wc_endpoint_url() ) {
      // Do you changes to $item_name here
      $item_name="New Item Name";
    }
    return $item_name;
}

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