Store POE2 vs POE1 how do you know?

so how do i know what item works in poe2 from the website store?
I see people running around with pets and stuff that are not in the game store, so i asked and they told me they got it from the website store. However, they said be careful not everything works for poe2. I came on the website and went to the store but there isnt anything saying what game it works for. So how do i know? if i want to buy something where does it says if it's available for POE2?

thanks