Vulcan has manipulated and the "cosmic magic." Based off of that he has the ability to manipulate magic on a more basic level because to him, it's like another form of energy.
That only means that god forbid attacking him directly. All the other options are free to use. Doing what Zee has done to Starbreaker for example is an one-way ticket to the Loserland for her.
As long as she doesn't try to blast Vulcan with blasts of raw magical energy, she wins...Vulcan isn't shown to be immune to transmutation for starters.
I think his ability incompasses magic, that includes direct attacks. I mean wether is coming at him, within him or just around him, he would be able to manipulate it.
Also if Zatanna were to ever harm Vulcan, he regenerates pretty fast and his threshold for pain is pretty damn high (being blasted to nearly some flesh and bone and still strong enough to try and choke out BB)
IMO Vulcan has a large tactical advantage due to the nature of his powers.
Thats true but isn't that energy trying to change the makup of what you are on a molecular level... Not saying I believe this but to vulcan magic = another form of energy.