Calling it right now - Ezra will be able to equip the Sith Holocron.
Either "You can equip blue villain upgrade cards in your deck - and you may equip Blue Upgrades to Ezra, regardless of character type".
But if that is the case - If a force choke legally finds itself in your deck - Could you then equip it to Luke Skywalker in theory? The Villain text on it only restricts which DECK it can go in, right?