I am not sure it works anymore.
I posted it was working in September 2020, just before OS 1.40 release…
Previewing Trigs with Midi input - Multimap on steroids? Confirmed working on DT and DN - #4 by sezare56
What about scenes with different slices (can be cycled waveforms) and different “synth” parameters ?
Dang, it must be something in 1.40 that changed the behaviour then. Thanks so much for double checking for me, I really appreciate it! 
Different slices could work for sure, though I’d have loved to be able to hold a trig and instantly change the wave cycle as well as amp and filter parameters while also riding the crossfader. That idea blows my tiny mind. But a man can dream…
Anyways thanks again!
A lot of changes in 1.40, including Trig Preview…
I gave it a try with scenes, seems interesting, may not suit you. Hold scene A with a toothpick !