I'll go with the experts here.
There is only a modest chance that any of the explosives are intact and viable. There is a only a slim chance that any of the detonators are viable.
Seawater immersion is a tough environment. It's difficult to intentionally design something that will last a few years in the environment. And this is wartime ordinance delivered on Liberty ships, which is built with the standard "if it even gets there, it will sit around for a few days before being used ...once". External drop tanks for fighters were made of paper and couldn't be filled with fuel more than a few minutes before departure because they would fall apart before they were emptied. Many types of shells had switched from bass casings to raw steel, with only a grease, oil or cosmoline spray. Aerial bombs and their fuses were built with similar standards.