No, there is indeed only one Drum Map available per MIDI track (so, as you have discovered, you can’t do what you were hoping to via MIDI Sends). But would it be impractical, for your workflow, to record-enable two MIDI tracks, each with its own Drum Map? If your MIDI drum Part(s) already exist, you could drag a Shared Copy onto the 2nd MIDI track.
(It is really frustrating that, in the Drum Map, an Input note can only be used once, otherwise you could maybe have combined all you need into a single Drum Map, the output side of the Map is indeed flexible enough )
OR (“left field” approach )…
Maybe you could indeed use a MIDI Send (in Pre/Record mode), and insert the Chorder MIDI FX to map the incoming note from there. (I’ll just go check, see if that is indeed possible )…
Yep, seems to work ok here… and, not necessary to put the Send into Pre/Record mode… the Drum Map doesn’t get sent to the Send in any case (unless you want to anyways )
(Purely for testing purposes, I had the MIDI track routed to Groove Agent SE4, with a basic kit loaded into it, and a GM Drum Map on the track. I then activated Send #1, routed to EZ Drummer 2 (once again, with just a basic kit loaded), so, normally, C1 would play the kick drum on both instruments, so, just for fun, i inserted the Chorder MIDI FX onto the Send, and remapped C1 to C#2, so that it would play the crash cymbal instead, and indeed, when I sent C1 into the MIDI track, it played, simultaneously, the kick drum in GASE3 and the crash cymbal in EZ Drummer 2.