They surely look like the real thing. They look like they have the alternating tentacle color, one tentacle purple, one yellow, etc...
with the african polypes all tentacles have the same color, start purple and end up yellow at the tip. The hornet don't have a mix of color in their tentacles and each tentacle have a single color, either blue or yellow.
That is the distinctive trait of the real purple hornets. I am glad to see they grew well for you under LED. Seem that it's probably the way to go with them then, because mine did not do well under T5HO and were growing slowly, then they were chewed up by amphipods
Can you tell me what LED you are using? also what strength?