Have a look at this section of DMarket to choose a CS2 tool and to buy it for your game. Some significant tasks can be accomplished with these tools – such as moving the StatTrak feature from one CS2 skin to another (the Swap Tool). You don't need CS2 Keys for it. Do not forget about the unique opportunity to trade CS2 skins and buy Dota 2 items directly on the DMarket platform!