It's probably one of the most fun and interesting matchups in the game, due to both characters having so many tools, but only being able to selectively use them. Probably 5-5 because they both have tools for pretty much every situation. First note, respect her frames (especially when she's in Shield Stance) and you'll generally be okay. Make sure you don't jump on her too much either. She has really good d2s in both stances, most notably Lasso.
From what I've played of the matchup (which is a lot, btw) Staff vs. Lasso and Escrima vs. Shield are your optimal situations. However, note that it is dependent on how the match is going, too.
Overall, in Staff vs. Lasso, you will need those j2s and Flying Graysons to keep her out of the air (j2 is better though). Staff pound is kind of useless until you make her realize that going up there carries a heavy price. It doesn't help that she can TK air charge into you to punish it from fullscreen too. A more rush-heavy WW won't be as much of a threat while you're in Staff because you'll be able to live at a range where her only real option is b2. Also, if she has you fullscreen while you're in staff, just switch to Escrima and get back in there.
Vs. Shield stance, I know it's tempting to play the footsies game with her using Staff. "Ha, mine's bigger than yours!" Yeah yeah, we get it. But in this stance, Wonder Woman stays grounded. She is begging you to play that game on her terms because that's what the stance is made for. You don't go in raw with your Dick. You use Escrima's mobility and ground spark to make her come to you. From there, you can start the footsie game because the ball's in your court; she's playing your game. Whip out Staff when she tries to challenge you, and then blow her up for her mistakes.
Additionally, if she is at a life lead and goes into Shield stance, do not stay in Staff and try to zone her. Matter of fact, don't try to keep her out at all; go in. Here, you'll need the mobility and buttons (j3, d1, 1, f2, b2, u3, etc.) from Escrima to get something going. Shield stance makes it very easy to wait opponents out at a life lead. Don't let happen by playing too patiently. You'll be able to save some extra meter in this matchup, too, in order to pushblock Shield, because you won't be spending a lot on MB staff pound. That move is not nearly as useful here as it is in other matchups.
As far as wakeups go, the most common ones are Lasso Spin and Shield Bash. Lasso spin is fully punishable with pretty much whatever you want (iirc), but Shield Bash can be MB'ed for +frames. If you can bait a couple of Lasso Spins and punish her, you should be good on that front whenever you get a knockdown. But definitely just respect her wakeups in Shield unless you have a setup to reverse them, or she has no meter.
The best way to prepare for this matchup are to play heavily in one stance and see how you can deal with what each of WW's stances has to offer. I used to play straight Escrima or Staff matches against the local WW player to work on what possible answers I had in any given situation. But it really does come down to who is the better player and has more knowledge of how both characters work imo.
That's pretty much it off the top of my head.
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