Nostalgik said:
First Chrollo, then Ging, now Kurapika too can copy abilities? *sigh* Togashi, why you running out of ideas? :(
Ging does not have a copying ability, he's just very good at controlling his nen and by analyzing how an opponent does something, he can figure out how to shape and control his nen in a similar way, if the opponent's ability is merely throwing a nen ball by instance it's not really that hard to shape your nen into a ball too and throw it if you are an Emission type, we don't know, but he probably ins't able to mimic more complex abilities though.
It's not different from Hisoka "copying" John Doe's disguise ability. There never was anything preventing someone from creating a Hatsu similar to another person's if they knew the theory behind it, they just don't it frequently because:
1-It may be from a different category which you are not proficient with, by instance, John Doe's scarf is Conjuration, being a Transmutter Hisoka can utilize it, but not as well as John Doe, which doesn't matters much considering the nature of the ability.
2-Just because you know the theory behind something, doesn't mean you'll actually be able to do it, by instance, you may know the theory behind riding a bike, but it still requires a few tries before you can fully grasp it.
3-Just because you can do something, doesn't mean you proficient in doing it, you'll probably not be able to use a copied ability as well as someone who has been doing it for years by instance.
Chrollo and Kurapika don't copy, they just steal a person's Hatsu and are able to utilize them as if they were their own, also Kurapika probably had the idea to create his ability after seeing Chrollo so there's that.
Ging is more like knowing the recipe to create a cake similar to another person's, Chrollo is like stealing an already made cake and claiming he did it.