No$GBA has stated that it can send some package at the WFC, but could not hold a game. Still it was written that it can emulate the Pictocha, but could only do the handshake (however it is written).
I guess it is not possible by now but will be possible sometime.
I remember that a homebrew said something about a DS-to-DS connection, but I do not remember right now. I guess that is a step for doing a multiplayer emulation on the DS (I guess this is offtopic).
Maybe we get a version exclusive for multi just like VBA did.