Why old Argentine battleships would struggle in 1982

What could Argentine battleships have done during the Falklands War?

Very little safely; their low speed and vulnerability to submarines, aircraft, shallow water, and coastal defenses would dominate the scenario.

The answer expects preserved Argentine battleships to draw immediate British air and submarine attention during the Falklands War. Sea Harrier anti-surface capability is treated cautiously, but Royal Navy submarines with heavy torpedoes would present an unmistakable threat. The old ships would be too slow to rely on maneuver against aircraft and could also be constrained in shallow water near ports and landing sites. Coastal batteries would add another danger if they tried to approach defended shores. Their nominal gun power would therefore be outweighed by vulnerability in a modern combined air, submarine, and littoral battlespace.