The Mopho sequencer cannot send MIDI. It affects the oscillator(s) directly as a modulation source.
The arpeggiator does not send MIDI because that would interfere with playback. Consider what would happen if you activated the arpeggiator, recorded some MIDI data by holding down a chord with the arpeggiator synced to external clock, and then played the recorded data back... if individual notes were transmitted and recorded, the playback would be really weird if the arpeggiator was still on.