comin from socal I can say that we have Warios crawling out the anus. At least, we used to. It seems to have died off, but we still have some of the best out here (Futile and Fiction).
So let's get the infinite out of the way first. **** is hard, no doubt about it. To perform, you have to grab release into the air (so no platforms) and then regrab with only a couple frames of error. There is no way (to my knowledge) of getting a guaranteed d-smash out of grab release. So in general, it's a pummel infinite. (and thus, not really worth it). BUT, we can still force air release, which means we can get guaranteed hits on him out of it (like ph00t stated). I personally like doing f-air, but I would also like to look into up-b, that sounds like a solid idea.
Now, as for the actual match-up.
in the air, Wario is a beaaaaast. his airdodge is above par, is aerial control is astounding, his dair is a **** multi hit and sets up for tons of stuff and autocancels easy, his nair has two hitboxes and ***** sauce. All of this combined with the fact that he can airgrab at any time (given 2 frames). Probably the only reliable way to encounter Wario in the air is with B-Air or U-Air, but be careful with U-Air, because if you jump past him you're going to get ***** (clap/anything he wants). He's got way too much air control to get hit with aerial side-bs on a frequent basis, and that same aerial control lets him punish you too.
As for the ground, just watch out for his f-smash and grabs really, I don't know any Warios that spend all that much time on the ground. You can punish a lot of his ground stuff with grabs so they'll be really hesitant to use them.
A big focus here is avoiding Warios kill moves. If you take away f-smash and u-air you can survive to a ridiculously high percent. Of course, watch for wafts at low percent, that can set the match into a "holy **** I need to catch-up" pace, which you really don't want.
As for edgeguarding, either way I doubt there will be a lot of gimp kills. I mean, Wario's f-air is a pretty good GTFO aerial, but he just doesn't have the vertical speed to catch up with ZSS. As for him, if he's forced to use the bike abuse the **** out of that fact and try to predict where he'll JUMP OUT of the bike. However, his aerial control means he'll raaaarely use the bike. Also, sidenote: his up-b can't sweetspot the ledge, so if he has to use it, d-smash the **** right out of him.
In general: this match is a ****load of u-smash. surprisingly enough u-smash is a ridiculously good move here. it's one of ZSS's only answers to Wario's aerial superiority, it'll hit through everything of his AND punish airdodges (if spaced properly). And once you've got Wario at a higher altitude it's easier to properly space u-airs and b-airs.
uhh yeah, I think that's it.