May be add virtual field to access state name in woocommerce

README.md

1. add new code to functions.php
2. use billing_state_readable instead of billing_state

functions.php

<?php
function add_readable_metakey( $value, $object_id, $meta_key, $single ) {
    // Maybe modify $example in some way.
	if($meta_key == 'billing_state_readable'){

		$country =  get_post_meta( $object_id, '_billing_country', true );
		$state =  get_post_meta( $object_id, '_billing_state', true );

		return WC()->countries->states[$country][$state];
	}
	if($meta_key == 'shipping_state_readable'){

		$country =  get_post_meta( $object_id, '_shipping_country', true );
		$state =  get_post_meta( $object_id, '_shipping_state', true );

		return WC()->countries->states[$country][$state];
	}
    return $value;
}
add_filter( 'get_post_metadata', 'add_readable_metakey' ,10 ,4);