To rename a flac tag I can copy it to the new tag (format value) and then do a remove tag of the old one. But is there a single action that can just rename the tag?
No, there is no "rename tag field" action type.
Thanks, Florian. What is the expected behavior of a Format value action on a flac file when there are multiple fields with the same name? For example:
Action type: Format value
Unfortunately, these actions do not support handling of multiple fields with the same name at the moment.