I’d be interested, but where would we even find audio of the Sith language? I can’t think of an instance of it being spoken in the movies. I guess KOTOR has a lot of alien voice lines, but I can’t remember any of them that sound like Palpatine.
Isn’t Movies Remastered in touch with this one guy online who can do an impression of Palps?
EDIT: Isn’t it Ian-Luke Production?