Animator.GetBehaviours

Возвращает все StateMachineBehaviour, которые соответствуют типу T или производны от T. Возвращает null, если не найдено.

using UnityEngine;
using System.Collections;

// An example StateMachineBehaviour.
public class BreathBehaviour : StateMachineBehaviour
{
    public bool  fastBreath;

    // OnStateUpdate is called at each Update frame between OnStateEnter and OnStateExit callback
    override public void OnStateUpdate(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        animator.SetBool("FastBreath", fastBreath);
    }
}


public class RunBehaviour : StateMachineBehaviour
{
    // OnStateUpdate is called at each Update frame between OnStateEnter and OnStateExit callback
    override public void OnStateUpdate(Animator animator, AnimatorStateInfo stateInfo, int layerIndex)
    {
        BreathBehaviour[] breathBehaviours = animator.GetBehaviours<BreathBehaviour>();
        for (int i = 0; i < breathBehaviours.Length; i++)
            breathBehaviours[i].fastBreath = true;
    }
}