Thanks.
Sorry - I forgot B3 V2 does'nt work in ALL mode, and MPE use multiple MIDI channels..
Other Arturia applications does have a ALL setting. So perhaps you can try it out in them. I assume it will also require the parameters can respond to ALL midi channels at the same time. I'm not sure that's the case.
I think only Pigments officially have MPE support - of some kind at least.
I also think that CS-80 work with at least polyphonic aftertouch. I understand, it has worked for some, but i have never had polyphonic aftertouch my self.
I can suggest you ask Arturia support, if you wan't an answer.
Perhaps it's just a way to work fast and easy, that the parameters is present. And perhaps thery are there just in case. Perhaps Arturia also prepere for MIDI 2.0. I can't tell.
I think Arturia will only teel you is it works now or not. perhpas they will tell you more, if they are absolute certain if it will arrive or not.
I don't know if anyone have it working. Perhaps someone will reply about that.
Best
LBH