It is possible to trade with other Players?
I test the Beta with my friend and we did not found any options to trade with items.
It isnt helpful when I only can sell my weapons and items that my friend need.

Nope you can't trade

You can't trade as of yet, but there is a trading system implemented.

Thing is, the trading system is a stall system and is restricted solely to paying players whether you are a seller or buyer.