AC-13828::Unable to place order with paypal express checkout when we are directly checking out from cart page

Author: glo60612

app/code/Magento/Paypal/Model/Config.php

@@ -607,6 +607,25 @@ class Config extends AbstractConfig
      */
     protected $cspNonceProvider;
 
+    /**
+     * Payment methods to skip address validation
+     */
+    public const PAYMENT_METHODS_SKIP_ADDRESS_VALIDATION = [
+        self::METHOD_EXPRESS,
+        self::METHOD_WPS_EXPRESS,
+        self::METHOD_WPS_BML,
+        self::METHOD_WPP_BML,
+        self::METHOD_WPP_DIRECT,
+        self::METHOD_PAYMENT_PRO,
+        self::METHOD_WPP_PE_EXPRESS,
+        self::METHOD_WPP_PE_BML,
+        self::METHOD_PAYFLOWPRO,
+        self::METHOD_PAYFLOWLINK,
+        self::METHOD_PAYFLOWADVANCED,
+        self::METHOD_HOSTEDPRO,
+        self::METHOD_BILLING_AGREEMENT
+    ];
+
     /**
      * @param \Magento\Framework\App\Config\ScopeConfigInterface $scopeConfig
      * @param \Magento\Directory\Helper\Data $directoryHelper

app/code/Magento/Quote/Model/CustomerManagement.php

@@ -16,6 +16,7 @@
 use Magento\Framework\Validator\Exception as ValidatorException;
 use Magento\Framework\Validator\Factory as ValidatorFactory;
 use Magento\Quote\Model\Quote as QuoteEntity;
+use Magento\Paypal\Model\Config as PaymentMethod;
 
 /**
  * Class Customer
@@ -159,7 +160,8 @@ public function validateAddresses(QuoteEntity $quote)
                 $quote->getShippingAddress()->getCustomerAddressId()
             );
         }
-        if (empty($addresses) && $quote->getCustomerIsGuest()) {
+        if (empty($addresses) && $quote->getCustomerIsGuest() &&
+            !in_array($quote->getPayment()->getMethod(), PaymentMethod::PAYMENT_METHODS_SKIP_ADDRESS_VALIDATION)) {
             $billingAddress = $quote->getBillingAddress();
             $customerAddress = $this->customerAddressFactory->create();
             $customerAddress->setFirstname($billingAddress->getFirstname());