magento-test/app/code/Magento/Sales/Test/Mftf/ActionGroup/SelectPurchaseOrderPaymentMethodActionGroup.xml

<?xml version="1.0" encoding="UTF-8"?>
<!--
 /**
  * Copyright © Magento, Inc. All rights reserved.
  * See COPYING.txt for license details.
  */
-->

<actionGroups xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:mftf:Test/etc/actionGroupSchema.xsd">
    <actionGroup name="SelectPurchaseOrderPaymentMethodActionGroup" extends="SelectCheckMoneyPaymentMethodActionGroup">
        <arguments>
            <argument name="purchaseOrderNumber" type="string"/>
        </arguments>
        <remove keyForRemoval="checkCheckMoneyOption"/>
        <conditionalClick selector="{{AdminOrderFormPaymentSection.checkPurchaseOrder}}" dependentSelector="{{AdminOrderFormPaymentSection.checkPurchaseOrder}}" visible="true" stepKey="checkPurchaseOrderOption" after="waitForPaymentOptions"/>
        <fillField selector="{{AdminOrderFormPaymentSection.fieldPurchaseOrderNumber}}" userInput="{{purchaseOrderNumber}}" stepKey="fillPurchaseOrderNumber"/>
    </actionGroup>
</actionGroups>