How to change label Firstname into Customer Firstname only on checkout/payment page in magento2.1.7?

Question

How to change label : Firstname to Customer Firstname

only on checkout/payment page for payment method ( ex:paypal, debit/credit card,cash on delivery) in magento2.1.7 ?

Answer 1

You can do this way. Create preference of class Magento\Checkout\Block\LayourProcessor.php

LayoutProcessor.php

<?php
namespace Vendor\Module\Block;
class LayoutProcessor extends \Magento\Checkout\Block\Checkout\LayoutProcessor 
{ 
 /**
 * Process js Layout of block
 *
 * @param array $jsLayout
 * @return array
 */
public function process($jsLayout)
{
    $attributesToConvert = [
        'prefix' => [$this->getOptions(), 'getNamePrefixOptions'],
        'suffix' => [$this->getOptions(), 'getNameSuffixOptions'],
    ];

    $elements = $this->getAddressAttributes();
    $elements = $this->convertElementsToSelect($elements, $attributesToConvert);
    // The following code is a workaround for custom address attributes
    if (isset($jsLayout['components']['checkout']['children']['steps']['children']['billing-step']['children']
        ['payment']['children'])) {
        $billingElements = $this->getAddressAttributes(true); // Fetch customer attributes
        $billingElements = $this->convertElementsToSelect($billingElements, $attributesToConvert);
        $jsLayout['components']['checkout']['children']['steps']['children']['billing-step']['children']
        ['payment']['children'] = $this->processPaymentChildrenComponents(
            $jsLayout['components']['checkout']['children']['steps']['children']['billing-step']['children']
            ['payment']['children'],
            $billingElements
        );
    }
    if (isset($jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']['children']
        ['step-config']['children']['shipping-rates-validation']['children'])) {
        $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']['children']
        ['step-config']['children']['shipping-rates-validation']['children'] =
            $this->processShippingChildrenComponents(
                $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']['children']
                ['step-config']['children']['shipping-rates-validation']['children']
            );
    }

    if (isset($jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']
        ['children']['shippingAddress']['children']['shipping-address-fieldset']['children'])) {
        $fields = $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']
        ['children']['shippingAddress']['children']['shipping-address-fieldset']['children'];
        $jsLayout['components']['checkout']['children']['steps']['children']['shipping-step']
        ['children']['shippingAddress']['children']['shipping-address-fieldset']['children'] = $this->merger->merge(
            $elements,
            'checkoutProvider',
            'shippingAddress',
            $fields
        );
    }
    return $jsLayout;
}

/**
 * @return array
 */
private function getAddressAttributes($isOnBilling = false)
{
    /** @var \Magento\Eav\Api\Data\AttributeInterface[] $attributes */
    $attributes = $this->attributeMetadataDataProvider->loadAttributesCollection(
        'customer_address',
        'customer_register_address'
    );

    $elements = [];
    foreach ($attributes as $attribute) {
        $code = $attribute->getAttributeCode();
        if ($attribute->getIsUserDefined()) {
            continue;
        }
        $elements[$code] = $this->attributeMapper->map($attribute);
        if (isset($elements[$code]['label'])) {

            if($code == 'firstname' && $isOnBilling) 
                $label = 'Customer First Name';
            elseif($code == 'lastname' && $isOnBilling)
                $label = 'Customer Last Name';
            else
                $label = $elements[$code]['label'];

            $elements[$code]['label'] = __($label);
        }
    }
    return $elements;
}
}

You have to override needed private members as well. Let me know if you need any more help.

Answer 2

Under payment method (debit/credit) Recipient Firstname to Customer Firstname and Recipient Lastname to Customer Lastname and so on. Refer my screenshot