Using WP_Query and WP_Meta_Query Outside of WordPress

This is what worked for me:

require_once 'wp-config.php';
global $wpdb;
$args = array(
            'post_type' => 'product',
            'posts_per_page' => -1,
        );
$Query= new WP_Query($args);

You can use similar way to achieve what you want.