Yes, As same as MONTAGE, MODX is fully compatible with the Yamaha MOTIF XF /MOXFsynthesizer.
MODX has 1 GB flash ROM for user waveforms
The following data can be loaded to MODX6/MODX7/MODX8 among all MOTIF XS6/MOTIF XS7/MOTIF XS8 data. Please note that the data is loaded as “User File” or “Library File.”
|.X0A||User Voice, User Performance, User Arpeggio, User Waveform|
|AllVoice (All Voice)||.X0V||User Voice, User Waveform|
|AllArp (All Arpeggio)||.X0G||User Arpeggio|
|AllWaveform (All Waveform)||.X0W||User Waveform|
Please check the official Yamaha Link :