#well. technically yeah

Does anyone else apart from Hilda and N know that Hilbert is a Zoroark? (Like the gym leaders, the elite four the champion etc)

Hilda's mom knows! The whole reason Hilbert initially stuck around is because she patched him up when he was injured after he got separated from his pack. Alder finds out at some point during the events of Black and White and is pretty chill about it.

Cheren and Bianca find out after the events of Black and White in a less than chill way