This video from LESINDES shows off the Dave Smith Instruments Prophet 12 Module being sequenced by an Arturia Beatstep Pro.
LESINDES says, the Prophet 12 is a very capable arpeggio/sequencer-expander... So many modulations. 4 oscillators, 4 LFOs, 4 envelopes...
More information:
Developments for Korg's instrument have been slow but promising.
Older Music Machines & the People Who Still Use Them