At the very start of the conflict the Argentine landings on the Falklands were spearheaded by a reconnaissance unit of Agrupación de Buzos Tácticos, APBT, Tactical Divers Group landed from the submarine Santa Fe.
Following on, were the Agrupación de Comandos Anfibios, APCA, Amphibious Commandos Group, who attacked the Moody Brook Barracks and Government House.
There were some actions as you can read in Wikipedia (links I put)... Some acitons SAS achieved victory in others Argentinian Commandos achieved the victory. In any case... actions were light.
Here you can see the skirmish at Many Branch Point between SAS and 601 Commando Company. In this case, it was an Argentinian victory.. but in the few skimirshes... there were all kinds of results: wins, losses and draws.
Special Forces are very similar in each country... the difference is not in individual level but in support (technical and combat) and in the material.