I have an instaced node in a script as it shown in the code below:
var instancedEnemyA = enemyA.instance()
instancedEnemyA.name = "Enemy"
instancedEnemyA.set_script(load("res://characters/enemies/Enemy_A.gd"))
get_tree().get_root().get_node("MainScene2D").add_child(instancedEnemyA)
and I have to call a variable :
var enemyNode = get_tree().get_root().get_node("MainScene2D").get_node("Enemy")
print(enemyNode.beat_power)