Pass Data Through PHP Functions
WP All Export supports the use of custom, and native, PHP functions in all export types. For regular export fields, you can click on the export field and then use the "Export the value returned by a PHP function" option:
If you're running a Custom XML Export, Google Merchant Center Export, or if you're using a "Custom export field", then you'll pass data through custom functions using the same syntax as WP All Import:
This syntax style is explained in WP All Import's Inline PHP documentation: https://www.wpallimport.com/documentation/developers/custom-code/inline-php/.