Snippet to remove recipient's email address in WooCommerce UPS shipment request. WooCommerce UPS Shipping Plugin with Print Label - https://www.pluginhive.com/product/woocommerce-ups-shipping-plugin-with-print-label/

functions.php

/**
 * Snippet to remove recipient's email address in Woocommerce UPS shipment request.
 * Created at : 16 July 2018
 * Updated at : 16 July 2018
 * PluginHive Plugins : https://www.pluginhive.com/plugins/
 * Gist Link : https://gist.github.com/xadapter/d572fe8d690605118c76d8f1ee23df94
 */ 
add_filter( 'wf_ups_shipment_confirm_request_data', function($request_arr){
	unset($request_arr['Shipment']['ShipTo']['EMailAddress']);
	return $request_arr;
} );