I think the core of this is pretty simple. Block vs Power use. Stating that one is immune to said neutralization would simply end up being a declaration (probably with FP expenditure).
The trick is the nitty gritty. Specifically, what is used to block vs what is used resist the block. A couple ideas:
1. Number of refresh spent=number of refresh blocked. You could roll fate dice for variety, I suppose. So if you purchased Neutralization [-5] you'd be able to block up to 5 points of refresh (give or take).
2. A cheaper power would be one where it is keyed off a skill. Say, Conviction. So it'd be Conviction roll to establish a block. Character must beat that block to use a single power.
It's an interesting idea, to be sure. I like the second option better. Designate skill, establish block. I'd probably cost it at -2 or -3 (would need to playtest). Have "enhancements" that would allow it to last longer, be more potent, affect a wider variety of powers.
I think this works really well in a system that has power origins, like Strands of Fate posits. So you could say that this could shut down Technological, Mutation, Alien, or Supernatural, then charge additional refresh to affect a wider variety of options.