As I recall rightly or wrongly when you first start posted about the onyx and sunburn missiles I read a very few things about them being in submarines. At times they talked of them as being retrofitted. There was also at least one mention of them being mounted on aircraft and I believe I saw a picture of an aircraft with an onyx missile mounted on it. However most of the times they were spoken of as surface to surface. Possibly all combinations are possible but the biggest tactical advantage is surface to surface because they elude radar by flying so low to the ground radar cannot detect them. Once they leave the cover of ground and can be detected by radar I imagine they become a much less menacing weapon.
If this is true Wow! Cuba can sink air craft carriers all the way to FLA.! Talk about defying American authority. NO Way Moscow is not prepared for a serious fight if they make a move like this.