Serial includes built-in support for a handful of Moxa UPort serial adapters, including the MCS7840 based 2210, 2250, 2410, and 2450, and as of version 1.2, the TUSB3410 based UPort 1110, 1130 and 1150 adapters.
Other Moxa UPort devices are not supported at this time. If you have one of the unsupported devices, please contact Moxa to express interest in a macOS driver for their other devices, and let us know as well.