I put 50% white shade cloth over my greenhouse and it seems to be working well. The plants grow the same or better. I'm at 2200' elevation 9b, so basically inland style California temps and stuff definitely gets burnt on those 100f days.
I don't have issues with annona in blasting sun, so, I dunno what to say - but all my eugenias and jaboticabas seem to appreciate the shade quite a bit.