AA has oneworld awards and 'All Airline Partner awards.'

oneworld awards are based on distance, allow one ways, and restricted to oneworld members of which at least 2 other than AA must be used. Only the distance between stopover points count. [refer to sticky in the oneworld thread]

'All Airline Partner awards' are based on zones, include OW and several airlines out of OW but are only designed for return bookings - one way awards cost the same as return awards. In rare occasions these awards can work out to be cheaper than oneworld awards.

Doesn't look like you can use a oneworld award for NRT-HKG because you'll fail the 'min 2 OW airlines other than AA' rule unless you want to go via another city like KIX.