This is less about gameplay changes and more about language confusion! For her Crescent Strike (Q) it states:
"Afflicts enemies struck with moonlight, revealing them if they are not stealthed for 3 seconds"
A better suggestion could be
"Afflicts enemies, striking the with moonlight and revealing them for 3 seconds. Stealthed champions will not be revealed." If that is the case.
Does the stealthed champion still receive the damage just no way of Diana to reveal them ?