Does anyone know if there is a way on the MOXF8 keyboard to have the ARP turned off for all patches including performance patches?

You don't give a reason, but certainly there is a way.

All Performances are in USER memory so you can change these as you desire and store them.

But to prevent arpeggios from triggering, since they all use the MOXF internal clock, simply set the MIDI SYNC = "external" and send in no clock information.
Press [UTILITY]
Press [F5] MIDI
Press [SF3] SYNC
Set MIDI Sync = external
Press [STORE]

Just FYI: this may cause some sounds (Voices or Parts) not to sound at all, because they are set to play from the arpeggio input only.

Cheers. That did the trick. My reason is that when I'm producing and I'm skimming through sounds I don't want it to trigger off any rhythm as it would clash with the track I'm making.

Thanks again.