No, they are different, because Acnologia is not a real dragon when the Dragons are real dragons, I am not saying Dragons have more resistance at all, just that they can fly which doesn't really require magic for them to use. Acnologia is immune to harmful magic that would hurt him, that is the whole point, he is still effected by magical effects but not to a considerable amount, yet he is a being of magic which would still effect him anyway. physically he may transform into a dragon but his existence is not a real dragon, just an artificial one which is different from other dragons, hence why they can be hurt by Dragon Slayer Magic and Acnologia cannot. I keep telling you that Face's power is a process which Acnologia still has some magic which is evident of his Dragon Form still active but is still effected from being drained of magic. Acnologia having wounds does not prove anything, just like Igneel having wounds as well, also, people can still bleed for a while when not attended to. DO you have visual proof that Igneel was shown to have caused said wound on his chest that made him go on conscious on the ground, and not it has to be an actual image of the actual attack that makes him fall, not the fall alone. Even Erza can survive interal attacks and same with Cobra and remain conscious even from other dragons, those are not minor attacks as well and they are still conscious. but in real life you do not have wings, a dragon physiology, stronger than the real world strongest human and survive flame attacks that can melt you to your bones. Natsu is definitely more powerful than standard Acnologia with different power ups via his Seven Flames mode and his power up from the Fire Dragon God. Acnologia lost because both he was immobilized and Natsu transformed into a dragonoid to allow his attack to bypass his defenses which is the only way to harm him. Actually, nothing suggests that his spirit would not be any more weak than his actual body since his spirit is immune to magic attacks as well in his physical form, so his spirit would operate the same way as his physical body would, his spirit form only existed to maintain balance with the Space between Time. Acnologia is not the same as Irene or Merc, As it is proven by his vary existence, Irene was still subjected to DS Magic, like with Merc but Acnologia is not, only by the harm of actual Dragons.