[saxsim]

If you long press a setlist on the setlists tab and select Share->Share song list, that creates a .mss file that does exactly as you describe. It's just the setlist and the list of songs. The other users have to have the same songs in their library (the names have to match). If multiple songs are found with matching names, it will then look at files to try to find the best match.

My solution is to implement something called song versioning. A song can have multiple versions where each version can have different files, cropping, annotations, etc. You can choose what version of a song to use for each setlist, and what version is loaded by default if the song is loaded by itself.

Such feature is not really practical. I would second the idea suggested by despe. I for example make songs for the whole band and it would be great if I could share the whole songs, not only setlists (because other band members don't have songs that setlist contains). So I prepare all the sheet music in Sibelius, print out pdfs and in MobileSheetsPro Companion I create songs, where all the sheet music could be imported and each bend member would only see the PDF according to the instrument they play (the role they choose).