Well, it is always difficult for foreigners to come to Japan. I think a lot of foreigners have a great image of Japan, and in many ways, this could be the country of your dreams (I've been living there for the past few years) but there's also a lot of problems to solve, and one of them is that the country remains relatively closed.
Therefore, I guess being deaf might be an other problem and I guess also that you don't know the Japanese sign language either?
However, I have a Japanese friend who happens to be deaf, so I'll ask him if he can give you some advices.
So I talked with my friend who told me that he's never heard of animation school devoted for deaf people. Therefore, you should maybe first learn Japanese. There are maybe some schools which teach in English but once again, they probably don't have any special policy toward deaf people.
Thank you for the comment and sorry for our late reply.
Like fremicourt3116 has said, learning the Japanese sign language will be huge help, but it will be challenging for sure. Keep studying Japanese is a good thing. Without any support system, learning new thing in Japan will be very difficult. Also, generally speaking, it's very hard for foreigners to land on good jobs in Japan without speaking the language at near native level. (English tutor is an exception.)
I'm sorry I can't be much of help. You might have a better luck with doing Google search with key words like 'support for deaf in Japan.' I hope you will be able to connect to the people in the similar situation.