I can think of two ways (at least)
#1
In edit mode (press E) you select the MIDI region > on the small keyboard on the header (left of the track) shift+click on a note/key (for example C2) > the respective notes on the region will be selected > press C and assign a MIDI channel to the notes > repeat for every drum piece (assuming you have 16 or less).
After that you route the MIDI track to a new bus, where you put at the very beginning a plugin to filter the channel you need. Duplicate the bus and adjust in the new ones the MIDI filter accordingly.
#2
you route the MIDI track to a new bus, where you put at the very beginning a plugin to filter the MIDI note corresponding to the drum element you need. Duplicate the bus and adjust in the new ones the MIDI filter accordingly.