Change Global Download Labels

The global labels, Download and Downloads, used throughout Easy Digital Downloads are extremely easy to change. Just use the simple filter function shown below:

function pw_edd_product_labels( $labels ) {
	$labels = array(
	   'singular' => __('Product', 'your-domain'),
	   'plural'   => __('Products', 'your-domain')
	);
	return $labels;
}
add_filter('edd_default_downloads_name', 'pw_edd_product_labels');

If you need complete control over each of the labels used for the custom post type, then read
this doc.