Aftertouch messages seem to have no effect on modulation.
This setup works:
This setup does not work:
iPad Pro 12.9 2018 v 15.5. Zeeon is up to date.
I found that out too and did some testing. It seems that the AU module blocks channel pressure.
If the midimixer module has two or more sources, it will also block channel pressure, other midi modules are fine
Thanks for checking @ZhouJing!
Looks like a Drambo issue @giku.