As you might be aware like all PMW formats are DMEE trees. Some of them are pre-configured by SAP. MT101 is one of those.
it's not necessary to use DMEE for the payment MT101 you can do by using the same using standard format with required modification and settings.
if you want to do the same by DMEE you can proceed as follows.
So to send a file transfer in format SWIFT MT101, you need only to define :
* a payment method (FBZP) linked to PMW using format MT101(as given by bank may be different as per country)
* a selection variant (OBPM4) for pgm SAPFPAYM and variant MT101
And you could launch F110 via pgm RFFOAVIS_FPAYM / RFFOM100/RFFOEDI1