Nope, because DSD+ provides both audio channels (Slot 0 and Slot 1) simultaneously as opposed to the older DSD which basically provided mono audio in a "first come first served" fashion, whichever channel started providing voice traffic first became what you heard.
DSD+ is a major improvement in that respect (personal opinion there, so take it as such) - the first time I heard both channels at the same time (Slot 0/Channel 1 in the left speaker, Slot1/Channel 2) in the right it somewhat freaked me out because for a moment I was so unused to it, being unexpected. I figured I had done something that was feeding back a second channel or something playing in the background through the other speaker until I realized what was happening and then it was the "Oh wow, how cool is that..." reaction.
Anyway, the -D1 or -D2 switches don't function at this time as I understand it, at least I saw mention of them in the past and the person testing it said it didn't work at all so the default is if you're monitoring DMR/MOTOTRBO traffic and there's voice comms happening on both slots/channels, you'll hear both conversations at the same time - and DMRDecode can verify what you're hearing based on group info, etc.
It's probably a feature the developer intended to add but perhaps decided nah, people would want to hear both sides anyway, they can edit the audio files for one or the other channels afterwards.