It is possible to make a mechanical angle bisector. Think of a compass for drawing circles but with a 3rd arm bisecting the angle. If you attach the bisector normal to a mirror, you can point one leg at the sun and the other at a target. An array of these would require linkages to aim all inputs parallel toward the sun and all outputs fixed toward the target - the outputs don't have to be parallel just have each pointing at the target. 2-axis actuation to move all mirrors as needed. Not sure if this has ever been tried, it's just an idea I had some time ago.