>>57235965That Black 2 is suspicious. Those plastic single-holder cases are all signature of a forgery, but I haven't heard of any gen 5 games being counterfeited at all. At least, ones that aren't immediately obvious. I don't remember why exactly though.
The top Platinum makes me suspicious too, just based off the price. I also don't see the down arrow, which should be emboldened on the cart. Probably not legit, but I can't tell from here.
The lower Platinum is a clear forgery. Fakes tend to have the down arrow engraved on them instead of emboldened on it.
That White also seems suspicious because only the case is shown. They could be selling anything in there.
I can't tell from that HeartGold. The price seems accurate for a real cart, but it's too unclear to make out.