Enables shipping calculations in PayPal
<?php
/*
 * Plugin Name: Easy Digital Downloads - Enable PayPal Shipping Calculation
 * Description: Enables shipping calculations in PayPal
 * Author: Easy Digital Downloads
 * Author URI: https://easydigitaldownloads.com/
 * Version: 1.0
 */

function pw_enable_paypal_shipping( $paypal_args ) {
	$paypal_args['no_shipping'] = '2';
	return $paypal_args;
}
add_filter( 'edd_paypal_redirect_args', 'pw_enable_paypal_shipping' );
To implement this snippet on your site, create a brand new, empty WordPress plugin and paste the above code inside.