Here is an aggressive line for black in this opening:
-Black is temporarily down a pawn but has good compensation as white can either lose a tempo by moving the bishop or trade the bishop for the knight leaving black with the bishop pair in what will be a fairly open game. -Black is controlling the center and white's knight on g5 also looks silly now and will gain black another tempo. -Black is also threatening to equalize the material very very quickly and has a lot of threats going forward if white tries to get too cute.
Computer suggests best move after this for white is bishop back to e2, and black is completely fine.
7. c4 loses the g2 pawn and white's rook is now on the run.
The main line after 5...b5 is 6. Bf1. It and 5...Nd4 often transpose.
I have won lotd of games with fried liver and I think there is no refutation!
But on the other hand lolli attack is much more sound.
I recommed you to play D4 first(in the key position of fried liver after Nxd5) and if your oppnont played a6,you will play Nxf7