You mean 'External Instruments' plug-in if I understand your request. This is possible. Supposedly it is 'the fix' for PDC problems and MIDI, although it becomes quite difficult to work that way on complex mixes that already have processing on them.
If you use Logic's External Instrument-Plugin to route the audio outputs from the external MIDI device, the audio stream from the MIDI device is sadly not compensated during playback.
But If you route the audio output from the external MIDI device to the input on the audio hardware and monitor them through the Logic Input Object, the audio stream from the MIDI device is compensated during playback.