I just discovered that an AFEnumerationSet has at least 2 tighter restrictions than a PI Digital State set. While the digital state Name is stongly recommended to not be blank, there is nothing stopping it. And a PI state set can have digital state's with different codes but the same Name. Here's an example of a state set I stumbled across today:
So state codes 1, 2, and 3 all have the same state name. And state code 5 has an empty string for its state name. Yet I cannot duplicate this PI state set to be an AFEnumerationSet because an AFEnumerationValue's name must be non-empty and unique within its AFEnumerationSet. For those considering importing their PI state sets over to AF, you will have to consider whether your PI state set fully complies with AF's restriction.