How to override system.xml core file in magento2

Question

I would like to change New order status text to something else at payment method section of magento2 admin.

Admin->Store->Configuration->Sales->Payment method->Check / Money Order

See attachment for better reference.

I know that i can change this by core changes but i would like to change this text without making any change in core file.

I am able to do this by editing system.xml

vendor/magento/module-offline-payments/etc/adminhtml/system.xml

Answer 1

Magento may load our custom system config and merge into the exist nodes. In our custom system config, we should try:

Tested on Magento 2.0.2 and 2.1.2

Vendor/ModuleName/etc/adminhtml/system.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:module:Magento_Config:etc/system_file.xsd">
    <system>
        <section id="payment">
            <group id="checkmo">
                <field id="order_status" translate="label" type="select" sortOrder="20" showInDefault="1" showInWebsite="1" showInStore="0" canRestore="1">
                    <label>Custom New Order Status</label> <!-- Custom label -->
                </field>  
            </group>
        </section>
    </system>
</config>

Remember to add overridden module - Magento_OfflinePayments

Vendor/ModuleName/etc/module.xml

<?xml version="1.0"?>
<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:noNamespaceSchemaLocation="urn:magento:framework:Module/etc/module.xsd">
    <module name="Vendor_YourModule" setup_version="1.0.0">
        <sequence>
            <module name="Magento_OfflinePayments"/>
        </sequence>
    </module>
</config>