Alright I will try and start all of these. I personally don't like this match up. If you agree or Disagree with anything please voice your opinion.
When you play this match up you need to be aware of the Haku players skill level. He has a lot of different options to punish Tao. If you can tell that he knows the match up be calm and patient for you will have to bait his counters.
When you play this match up be very careful. Hakuman has 4 normal's you can crawl under on the ground. These are 5A, 2A, 5B, and 4C. In the air you can crawl under j.A, J.C, j. 214B. Whenever Hakuman goes for air dash j.2C > 2A. Block j.2C then Duck 2A for a punish or to triple jump out of the way. This is very common setup for any Hakuman. If the the Haku is smart enough to catch on he will replace 2A with an 6A so be mindful.
Next Whenever Haku is trying to zone you out with j.C or 4C. Time your dashes to crawl under these normal's for a punish. If you get caught in the corner watch for j. 214C, however if your opponent goes for J. 214B crawl under it and hit 5B for a counter hit in the air if you are fast enough. Otherwise he will be able to block.
Whenever you go for a mix up be ready to block. Haku counter, 5A, 6A and 2C await you on any of Tao's airborne mix ups. If you find yourself being read. Calm down and try a mix while already blocking to try and throw the Haku game. This can be achieved by using 2A every now and then to keep them guessing.
As for Haku block strings. A lot of it revolves around 5A and 2A. both of these can be crawled under. However pay attention. Depending on the Haku skill level he will bait the crawl and punish with any of his specials on the ground or with 3C and 6B.
Lastly if you see that the Haku is breaking by just trying to counter everything throw in a lot of grabs to really confuse him. This is not very good match up for Tao keep that in mind