In order to make that work you'd need to loosen the screws holding the frame to the masonry, plus cut the sealants on both the inside and the outside - and re tighten and reseal afterwards, of course. Also bear in mind that the frame has a solid head conecting the two stiles which is going to resist any attempts to adjust the frame. Shimming the sash hinge is probably a bit easier, to start with, but I think any work you do will need to be on that sashI might see if I can shim between the frame and the wall...