Gaming edge is just marketing. Wifi means it has an onboard integrated wireless adapter so you don't need to use an expansion card or USB adapter to have wireless capability if you prefer to use wireless rather than Ethernet.
Is there a specific reason you want to use X570 rather than B450 or X470? Are you planning to buy a PCIe 4.0 M.2 drive? Or several of them? Because if not, then you are probably just as well off saving the money and buying the B450 Tomahawk instead. Even if you want to use multiple PCI M.2 drives, the B450 or X470 Gaming Pro carbon might be a better, cheaper alternative. The X570 boards are expensive, and tend to actually not be that great unless you're willing to spend significantly more money for a very high end...