Spacex's Dragon and JAXA's HTV are currently the only vehicles that can bring unpressurized cargo in addition to the pressurized one inside the vehicle.
In the odd event that the ISS urgently needs more in-station cargo than can be carried inside the pressurized modules of the dragon or HTV, could we send part of it as unpressurized cargo, and it would then be secured through an airlock with the help of a robotic arm or an EVA?
Are things on the External Stowage Platforms ever taken inside?
How often are things from inside the station taken outside? (maybe like hand-deployed satellites? Please do not include EVA suits themselves in answers to this question)