Last Epoch will not have direct player-to-player trade, as far as we know.
There will be a RNG Loot Bazaar where you can randomly see random items from random players with absolutely 0 control over what you see and which players’ listings you see. It will essentially just be like a real-life flea market. You have no idea what will be there, but you might walk away with a fishing rod and a cool mug.