The trouble with this is that whatever steganographic feature you're embedding it into would (likely) not be uniformly random by default. So although nobody could prove you were transmitting an EC point, they could reasonably assume you were transmitting some form of encrypted data, given enough samples.
I think steganography is the right idea in general, but it needs to be more clever than the classic text/image-based techniques.
I think steganography is the right idea in general, but it needs to be more clever than the classic text/image-based techniques.