Which Second World War ships could still serve

Could any Second World War warships still be useful to a modern navy?

Sloops could still serve in patrol roles, while some later carriers might be adaptable only after substantial modernisation.

Modest presence missions demand less from a ship than high-end naval combat. Second World War sloops could still perform fisheries protection and routine patrol work where speed, sensors, and survivability demands are limited. Some later armoured aircraft carriers might retain enough structural strength to bear modern aircraft weights. Turning one into a useful aviation ship would nevertheless require extensive changes to machinery, systems, flight-deck arrangements, and support facilities. A surviving hull can be relevant even when modernization is expensive and unsuitable for front-line combat.