I would call it the same thing we call the circuit from a string inverter where the AC output terminates at a 2P-20A breaker, an inverter output circuit. This figure is the only thing in the NEC that describes an inverter output circuit as a branch circuit, so I think it's a little weak to support the idea that the NEC has defined this as a branch circuit.
Inverters are not utilization equipment. From 100:
Utilization Equipment. Equipment that utilizes electric energy for electronic, electromechanical, chemical, heating, lighting, or similar purposes.
Inverters are primarily an energy source, not a load. Branch circuits power loads, if it's not a load it's not a branch circuit.