WooCommerce - Customer account: Enable "Label" for billing and shipping address

woocommerce-customer-account-enable-label-for-billing-and-shipping-adress.php

// Billing Fields.
add_filter( 'woocommerce_billing_fields', 'custom_woocommerce_billing_fields' );
function custom_woocommerce_billing_fields( $fields ) {
    $fields['billing_address_2']['label'] = 'Address 2';
    $fields['billing_address_2']['label_class'] = '';
    
    return $fields;
}

// Shipping Fields.
add_filter( 'woocommerce_shipping_fields', 'custom_woocommerce_shipping_fields' );
function custom_woocommerce_shipping_fields( $fields ) {
    $fields['shipping_address_2']['label'] = 'Address 2';
    $fields['shipping_address_2']['label_class'] = '';
    
    return $fields;
}