Dynamically change text of button/menu item

I have a command to create a zip file named after the current folder:

Copy ARCHIVE HERE CREATEFOLDER="{sourcepath|nopath|noterm}" WHENEXISTS=rename

However, I'd like the menu item for that command to say "Copy to ZIP blah.zip" where 'blah.zip' is effectively the {sourcepath|nopath|noterm} part.

I've had a search around and see this was requested a while ago, and that we have the ability to change the icon with @icon, but can't see anything for the text yet?

(as an aside, WHENEXIST=rename also doesn't do as expected, but that's probably a mistake on my part)

You can use %2 in the label to insert the name of the first selected file (without path or extension).

However, this only works in context menus, not in toolbars. I don't think there is a way to change toolbar labels dynamically. (It's mainly for performance reasons, but a mechanism to do it for specific buttons isn't out of the question.)

It is context menus I'm looking at, but I need the name of the folder the files are in, so looks like that's not possible at the moment. Thanks anyway!