WooCommerce Required Fields

wc-functions.php

/** Change obligatory-optional status on billing fields
 * true = required
 * false = optional
 */
add_filter('woocommerce_billing_fields', 'force_billing_fields', 1000, 1);
function force_billing_fields($fields) {
	$fields['billing_first_name']['required'] = false; //First Name
	$fields['billing_last_name']['required'] = false; //Last Name
	$fields['billing_email']['required'] = false; //Email
	$fields['billing_phone']['required'] = false; //Phone number
	return $fields;
}
/** Other billing fields
 * true = required
 * false = optional
 */
add_filter( 'woocommerce_default_address_fields', 'customize_extra_fields', 1000, 1 );
function customize_extra_fields( $address_fields ) {
	$address_fields['company']['required'] = true; //Company name
	$address_fields['address_1']['required'] = false; //Address
	$address_fields['country']['required'] = false; //Country
	$address_fields['city']['required'] = false; //City
	$address_fields['state']['required'] = false; //State
	$address_fields['postcode']['required'] = false; //Postcode
	return $address_fields;
}