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Practically every turboprop made that isn’t running Garretts will auto-feather. And many recips as well (provided it has a constant-speed propeller).

In most turboprop engines (except Garretts) and most recips with constant speed propellers, engine oil pressure delivered to the propeller dome drives the propellers OUT OF feather. Which means when you shut it down, it automatically goes to feather. If the engine poops the bed in flight, as oil pressure falls off, the prop goes to feather automagically.

Garretts are different (and AFAIK it’s only Garretts, but I might be wrong). They need oil pressure to drive the props INTO feather. Shut a Garrett engine down and its props go to full pitch. So if the engine dies, you have a limited window to feather before there’s no oil pressure.

The only legitimate reason for both being feathered would be a double engine failure. But those are exceedingly rare — like drawing straight flushes two hands in a row rare — except in cases of fuel starvation.

All of the US Navy’s aircraft are multi-engine except maybe some reciprocating engine trainers and the F-35. And they still lose an airframe on average once every 3-4 years due to fuel starvation. And they should know better.

That both props were feathered could mean somebody who shouldn’t have feathered an engine that didn’t need it. The engine-out emergency procedure would have had a guard against that very occurrence, but that’s why they put the “human” in human error.

The determination that both engines were feathered probably was made by examining the position of the control levers in the cockpit. If they’ve been over the wreckage in that detail, that means they’ve also already checked to see if the fuel tanks were dry. That there was no mention of fuel starvation would give me to believe the evidence ruled out that possibility.

Whether that means they crashed with one operating engine, who knows?