Greek pre-dreadnoughts as deterrent escorts

What use could Greek pre-dreadnoughts have had if they escaped Alexandria?

They would be useful convoy escorts, especially if improved fire control made them dangerous enough to deter a raider.

Convoy protection depended on deterrence as much as victory in a ship-to-ship duel. Even an old battleship with credible fire control could threaten a Deutschland-class raider at the ranges where it was being hit. The escort only had to make an attack costly enough that the raider looked for easier prey. Greek ships in that role could also free R-class battleships for other duties, although later Japanese entry into the war would make their likely operating area more dangerous.