It's the View Script Variables plugin. It shows all available variables, including the _hidden ones.
To get all the extra artists variables from the screenshot available, you need to activate the Additional Artists Variables plugin.
Ok, sounds strange, but I am no expert in using non-latin characters.
I only brought this suggestion up to show that it is possible with Picard to retrieve both original script and romanized version for many artists.
With scripting you can then decide what variable(s) from Picard you want to use to populate tags for use in MusicBee.
I'll check this plug-in out.
Thanks for advising it...
...or should I curse you for giving me more possible work!?
