No, well at least not yet.
The GBA universal link cable is the only way to link two GBA's together, sadly.
Yes.
To connect a Game Boy Advance (GBA) link cable to a Nintendo DS, you need to use the DS's GBA slot, which is located on the bottom of the device. Simply insert the link cable's connector into the GBA slot, ensuring a secure fit. This allows for gameplay features that utilize the link cable, such as trading Pokémon between compatible games. Note that the Nintendo DS only supports GBA link cables with GBA or GBA-compatible games, not DS games.
no. but maybe you can play GBA games on the 3DS with a R4 or a supercard.
GBA cable link
Not long at all once you have both GBA's connected initiate the link by going upstairs in any Pokemon center on both GBA's and talk to the trade center, colosseum or record corner lady to start the link!
Yes but you also can trade using a GBA to GBA link cable.
Right click on The Screen and click on link. :]
Yes. You must use the gba-gc link cable.
eBay
Unfortunately, GBA Link cables cannot be fixed. Once they are broken, they are broken. You must buy a new one.
Try gba4ios, it is much better, faster, easier to install, and has more functions.