As far as I can tell you would have to beat his endurance for each individual aspect. This is mostly based on my understanding of the maneuver action when it's opposed and then how magic interacts with that, but then again that's based mostly on evocation as well, so there's no hard and fast answer.
If applying aspects to an opponent via maneuver, you'll need to beat the resisting roll for each maneuver. That may not be endurance - a weakness spells might be opposed by Might, clumsiness by Athletics, etc.
If swinging blind, it's probably easier to apply aspects to the yourself, an ally, or the scene. But when you know an opponent well enough to target a weakness...