This is a bit of a favorable matchup for Baiken.
This matchup mainly revolves around:
Poking at midrange with f.S, 2S and Kabari, since her only move that beats them cleanly is the ice spike (236H) and they stuff raw summons
Using really low IAD Tatami and IAD jS to tatami, since it kills her summoning bubbles in the air and raw summons on the ground.
Chasing her down when she is using her air-movement to escape, with jP, iad jS and dashes (and antiair with jP or 6P)
Knowing how to escaping her mix-up game
The way to go about is first and foremost stay on the ground, mixup up with dash fd-break / dash 2s and kabari. Since these options either close the gap and
The goal is to deny Dizzy from summoning stuff, and thus force her to rely on ice spike-counterpoke (that is why you have to mix up with dash fd-break, so you can punis it on block with either Ouren ir iad jS jP jK -> combo).
Her 2H is also really risky for her, block and punish. Yet again, this is why you also dash up and block. The poking with 2S and kabari is to force her to use these risky moves and punish them. Because when you have forced her into the corner with a knockdown; she should have a difficult time getting in a favorable position again. Just try not to be a idiot and use well thought out pressure and positioning.
The biggest hurdle you wil encounter in this matchup is when she has gotten a knockdown (ex. she hits you with a ice spike) or she succesfully reads your passive play (ex.you are baing ice spike with block, but she does a raw-summon instead) and gets a summon. Generally speaking, killing the fish is a bad idea, but sometimes using 6P to kill it and then jumping or using kabari can be an idea. It (of course) depends on where Dizzy is on the screen and what she is doing. If she is stupid enough to use an air-based okizeme (ex. iad-stuff), just Ouren out of there and get into a favorable position. The real trick is when she starts abusing her retarded throw range, since the only thing you can really do is to either break the throw or 1f jump of there (which a lot of times leads to you blocking a laser or a fish attack, and then you have to block her c.S since she option selects her throw, which then puts you in yet another unfavorable position).
There are also some details regarding how to react to 2p, 2p 2k, 2k 2d into jc etc. but I'll save that for another time...
This matchup is focused on Baiken chasing down Dizzy and forcing her to use moves that needs tension in order to be safe (ice spike, 2h frc).
Dizzy has few defensive options, her best often being IB into 1f-jump and running away.
If Dizzy uses air-based okizeme, Baiken can just run away,if dizzy is on the ground and mainly abusing her throw-range, shit is tough for Baiken.
Dizzy has to use risky moves in order to beat Baiken, and if she guesses wrong she can die a quick and horrible death (ex: blocked 2H into BA 5H Kabari leads to huge damage knockdown and tons of tension for Baiken).
Baiken needs to be good at positioning herself well when chasing Dizzy, but is doable with experience.
IF BOTH PLAYERS ARE DECENT ENOUGH!
Yet again; I'll keep this post short, as I could go on forever when it comes to matchups against at least half of the cast. There are a lot of details and specifics as always, but I'll focus on the general stuff.
"Venom, No thinking button pushing is strong" - N-O on Venom vs Jam