Yes, defiantly not saying that's not how these work, and I do know that large boats tend to be direct drive. I'm just pointing out that most engines could do this and the limitation is generally how it interfaces with the external components and not as much a function of internal combustion type engines.

For example, a transmission would expect the engine to always run in the same direction, but given correct fuel and ignition timings, it doesn't really matter which way the crankshaft is turning while things are running.

I accidentally installed an injector pump 180° out of time on a MB OM617 and it "ran" kinda.. with a massive white smoke screen. I was shocked it even started.