Research: GBA - USB - USB - GBA

So I've been thinking a lot about whether it would be possible to link two GBAs over the internet (With the aim of playing Pokémon online). How cool would it be to be able to connect a GBA to a phone or computer and play online? The first step would be getting two GBAs to connect locally over USB. This project hints at that possibility but I need to do more reading about USB specifications.
Before I start investing my free time in this, does anyone know of any reasons why this would not be technically possible?

Why wouldn't it be technically possible? People are hooking up their old crap to their computers with modded USB-to-crap cords all of the time. You'd have to write a program or phone app to facilitate the link.

I just know that raw USB programming is A PAIN. You'd probably want something like an FTDI chip or so for hooking up hardware to your PC because they usually come with virtual COM port drivers which are very easy to write programs for.
There is two main solutions you could use:
- Simply sample the eletric signals at a very high rate over the internet (probably unstable and requires high data rates)
- Interpret the link signals correctly and send some kind of data packages over the net. The protocols are described at the usual place:
http://problemkaputt.de/gbatek.htm

In the end, you'd need basics about electrical engineering and if you got these, it's probably not that hard to make something like this.