To tell the truth, there is nothing to distinguish except A/X. As long as it is a big design and trademark, it is fake. Usually very low-key. Then go to the specialty store to buy it. Buy a few more and you will know.

I want to buy it online. Unless I buy it second-hand, there are few genuine products.

It sounds as if everyone knows that the store is expensive, but don't buy brands if you want to be idle.