[itsme]

A filter for songs with annotations would be great.

The transposing topic is a little more difficult, just resetting chords to what is in the file would not help.
Let me show a detailed example:
I use collections for bands / line ups and set Keys: in the database correctly.
A File_X.pro for Song_X contains chords in G
File_X.pro is used by Song_X1 in Collection1 with the original chords in G, Transpose 0, with Keys:G in the MSP datatbase
Song_X2 in Collection2 also uses File_X.pro but transposed to A. So transpose is +2 semitones, the database entry for Song_X2 is Keys:A.
Now, in a session or rehearsal context, someone asks for Song_X in F. I just open either Song_X1 or Song_X2, transpose to F (-2 semitones) with a few clicks and play. That was easy. The session goes on and later I don't remember what I transposed to what.

The task now is "find all songs where Keys: in the database doesn't match what is displayed".

To fulfill the task it would need:

Go through the database and investigate every ChordPro song.
For every ChordPro song do
1.) Look into the file and detect the key as MSP does it when a chordpro file is imported:
"Detect Key By: First Chord / Last Chord / Chord Progression" in MSP settings and the ChordPro tag {key: or {meta: key have to be considered.
2.) Probably also {capo: should be taken into account, but I'm not using a capo so don't know much about it.
3.) Apply the current transpose setting from the database.
4.) Compare the resulting key with the Keys: entry in the database.
If it's different, add the song to a "list of songs with incorrect Keys:"

Show the list.

Automatic correction is not possible imho in a helpful way.
I would like to handle it manually song by song after choosing one of the following:
- revert the changed transposition
- add another copy of the song in another (differently transposed) key
- change the chords in the file
- correct the Keys: database entry
- leave it as it is
- ...
MSP might help with an option to create a setlist with all the songs from the list. A unique name for that setlist could be created automatically.