I just realized I didn't respond to your hearing issues: I generally don't think that these would be a problem for learning martial arts. Of course it depends on your teachers teaching style, but generally they show you what to do and that is the most important part. They might have a metaphor or say for how long the next training sections go, but if you can read lips, you should be fine. The essential stuff you can only learn by watching and doing it yourself.

At first it's hard to follow what's being demonstrated, but you will get better at that fast. The beginning is always hard and you will feel like you're slow and clumsy and stupid, because everybody else doesn't seem to have trouble. That is completely normal and everybody there knows it, so don't worry! As soon as you've had more practical experience your mirror-neurons will help you translate what you see into what you need to make your body do.

Also if you let your teachers and training partners know you're hard of hearing, I'm sure they will be happy to accommodate. Everybody is there to improve and help others to improve as well. If they aren't, that's a huge red flag. Go find a better gym.