Can .xcconfigs be used with .plists other than Info.plist?

If I define some values in an .xcconfig then I can use those to supply a value to an element within Info.plist, but if I try to do the same for a .plist with any other name then it doesn't work. Is this some sort of hard-coded constraint?

(I can't move the elements out of the custom .plist into Info.plist as its being read by a 3rd party framework)

Can .xcconfigs be used with .plists other than Info.plist?
 
 
Q