All the questions I saw asked about ALL unreleased HAs, not just the ones we know of.
This question is probably kinda confusing so let me give an example:
We know Tyrantrum's hidden ability is Rock Head, and Typhlosion's hidden ability is Flash Fire, but these are both unobtainable through normal circumstances. What are ALL the Pokemon that have this quality?
Contrary Serperior, Reckless Emboar, Shell Armor Samurott, and Adaptability Dragalge are all released as of ORAS. So those don't count.