This is definitely a 6 to 4 in yukikos favor. Like everyone says, its mostly a waiting game, and a patience game till you can get hit. If you are playing a good yukiko, she will probably try to go for the unblockable setups which require her to use SB agi. You can short hop > jb out of it if timed right, but this is, again, hard to pull. My general advice is to IB as much as possible and wait for a good moment to use an assault counter to get some space. You can also troll her really hard if they are DP happy with EX hook> corkscrew to get a cool 5ish K combo (she can cancel her dia into agidyne though so mind her SP). If her persona is broken most yukikos will jump back and throw fans, you can use a lame roll OR DO THE SUPER AWESOME EX PARRY INTO CORK 'cause fatals.
I think pretty much everything that needed to be said has been said already... its a game of patience. If you play your cards right you get a chance, but general battle flow dominance goes to yukiko. Only reason aki gets a 4 in that matchup is because of hsi comeback potential like dacidbro said. If you are patient and you get a lot of SP off of that, your comeback game becomes all the more frightening. :v