When I do multiple versions of a piece in different keys, I create a text block at the top indicating the key. When I change the key, the text block stays the same. Not good.
I would like to do an insert to the text block, much like the composer's name, which inserts a specific measure's key (in my case, this would be measure 1) as text. Due to language differences, this would need to be functional similar to the chord tool (e.g. to enable "H-Dur" in German).
The same should be possible for expressions.