How to create AppleInternal variant on macOS?

It seems that AppleInternal folder is only working for Simulator to get debug menus etc.
One has to create file under /System/Library/CoreServices/AppleInternalVariant.plist. I know for recent macOS installations this is a sealed Volume (cannot change). Is there any trick how to create this file?

#if !TARGET_OS_SIMULATOR
#define INTERNAL_CONTENT_PATH "/System/Library/CoreServices/AppleInternalVariant.plist"
#else
#define INTERNAL_CONTENT_PATH "/AppleInternal"
#endif

Link to source code defining AppleInternal

The content of the file:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>AppleInternal</key>
    <true/>
</dict>
</plist>

Link to AppleInternal plist file

PS: Creating AppleInternal folder under Data Volume does nothing (during recovery).