Expanding directory variables in a non-WiX file

Question

I have in a WiX .wxs file:

    <Directory Id="TARGETDIR" Name="SourceDir">
        <Directory Id="$(var.PlatformProgramFilesFolder)">
            <Directory Id="INSTALLDIR" Name="XXX">
                <!- ... -->
            </Directory>
        </Directory>
        <Directory Id="CommonAppDataFolder">
            <Directory Id="CommonAppDataManufacturerFolder" Name="XXX">
                <Directory Id="MyAppFolder" Name="Blockchain">
                    <Directory Id="MyAppMainDataFolder" Name="data" />
                    <Directory Id="MyAppKeystoreFolder" Name="keystore" />
                    <Directory Id="MyAppLogFolder" Name="log" />
                    <Directory Id="ConfigDir" Name="configs">
                        <Directory Id="GenesisDir" Name="genesis" />
                    </Directory>
                </Directory>
            </Directory>
        </Directory>
    </Directory>

Now I want to install a file (e.g. a text or JSON file) with the variable $(ConfigDir) in the file's text replaced by its value based on the above WiX file. Possible? How?