I meant it hits her, but it doesn't do much damage.
If she starts ducking your 66As, nail the bitch with 66B BE to make her cut that out. If she starts to sidestep 66B, nail her with 66A.
As for Cervy, I agree he is nasty vs Ezio. Besides the attacks you've mentioned, there is also that downwards strike with both swords in one hand. The push back on that thing is very frustrating. It keeps Ezio on a terrible range, so Cervy can go to town on him.
After blocking 33B, pushing buttons is generally suicide because it's only -3 and it forces crouch. Trying to attack afterwards usually results in him backdashing your attack and you eating a 3B or iGDR. You should step this move as much as possible, especially if he starts doing it in succession.
Ezio's AA whiffing when trying to punish Cerv's 3B is really annoying. You guys might want to take a leaf out of Aeon's book and do K punishes instead. CE punish whenever possible.
For aB (which is a completely retarded move) you might be able to punish at your absolute closest range with 6B or 6K. I know Yoshimitsu can land 6K at absolute closest range so if 6B BE works, this can help the matchup a lot. CE might work from better ranges. Another trick you might want to try is "punishing" by whiffing the first couple of hits of 1BBB. I know I'm not the only one who sees the first two hits whiff and pushes a stupid button that results in the 3rd hit CHing.
Twitch ducking is suicide against Cervantes, but if you read the 1AB, punish the hell out of it to discourage him from using it more. You can get 66BB, 44K, or 1K.
Versus Siegfried, I don't really have much trouble with Ezio. After blocking 3(B)/WR (B), quickstep into A+B beats all immediate stance options. If he starts realigning his attacks in stance, you can 6AAB or 3B, which will get you a CH because the realign will make his stance attacks come out later. 3B and 6AAB also beat SCH B and SCH A but lose to SCH K after blocked 3(B)/WR (B) and you will net CHs. If he starts cancelling stance (which makes A+B blockable) you can hit him with 66BB.
44B and 2A+B are excellent ways of discouraging wakeup WR B. Once you get that out of the way you can work the 11K/22K mixup.
Also, whiff punish/JG punish as much as possible with 6B BE.