This seems to be the premise behind the PRC's
GJ-11 UAS. It is shrouded in secrecy at the moment but to my untrained eye, it looks unnervingly stealthy. If your SAG wasn't protected by a robust BARCAP I could see it being very difficult to deal with. Plus, if the result of
not dealing with it is an incoming ASBM salvo, then the stakes just get that much higher, but I digress...
AFAIK this is kind of how LRASM is supposed to work. It has its own onboard ESM system which allows it to passively narrow down the location of its target before it descends to a wavetop terminal approach and completes the endgame with the help of its IIR seeker. Theoretically, you might be able to use missile-to-missile datalinks to get a given salvo to act as something of a hunting pack, sniffing out the target before they collectively go after it. While I am not sure if this sort of thing has been implemented in the LRASM, it wouldn't surprise me at all - IIRC some of the old Soviet AShMs used to do similar things.