Is It posible paly with duo players

First of all its damn good to be back after 2 months, everything has changed.
Now back to the point is ti posible to play a two player game (Game link style) with another gameshell or with a device wich has the same emulator.

That all depends on the game and the emulator. The GameShell hardware is capable of making a connection between two boards over WiFi or Bluetooth for example. And a quick trip to Google shows there are emulators that support netplay over WiFi/Bluetooth.