Of course!
Once you installed player, wks, or server you created 2 more networks in your computers field of view, so now it has at least 3.
It has 1 or more physical networks (one of which is bridged)
It has a subnet private to itself for NAT
it has a subnet private to itself for Host Only
As a result, as long as your guests occupy the same subnet, they already see each other. So, if both are NAT they both live on the subnet, and can see externally out beyond your PC what ever your PC sees as if it were your PC. If its Host only, they can see each other and your PC, but nothing further.