Hi there, it is impossile to link up a trade between your android and gba cart, but it is possible to get your save file from your android to your gba cart. First off you would need a ds lite or original as is has the gba slot and you need a slot 1 flashcart like the r4 or something similar...
I didn't know they made an MSU cart for the Genesis.... I knew about the SNES one and the library for that is rather large but the Genesis one has very few games