Firstly, you need your Psychiatrists or therapists consent that an emotional support animal would benefit you.
It really depends on the person and what they do when they are angry. Not all people with anger issues are violent or would ever hurt an animal. Some internalize their anger.
For some just being able to get away with a dog that unconditionally loves you helps to mellow out your mood again.
It doesn’t harm the dog to be pet by you or for your frustrated tears to soak it’s coat as long as you don’t mind them licking your face to try to cheer you up or delighted to get belly rub time!!!!
If you are a violent or outwardly explosive person when dealing with your anger then a more physical release usually helps. Some take up running, boxing, martial arts, dance, gymnastics, cycling, swimming. Whatever can safely help you get out the adrenaline until you cycle back to a calmer state.
My daughter, an adult now with autism can be explosive and loud. My service dog and hers are trained to jump on her to distract her from self harm and to lick her face. She is completely non violent towards them and can’t help herself but to sink her hands into their soft fur.
The difference is though the dogs are service dogs and have been trained in what to do and conditioned through positive reinforcement that her loud screaming means affection time. They aren’t afraid at all, it’s party time!!!!
So what the person with anger management needs really depends on the person.