sorry, I still dont understand what you mean…
orac is modular at the synth/fx level rather than oscillator/env/filter/vca level - if thats what you asking
so, if you mean, can you just ‘replace’ the envelope type by a particular synth module, with another, then the simple answer is only by editing that module - so copy that synth module, edit it, add the env type you want.
if thats not what yo means, then back to basics:
what musical purpose/effect are you trying to achieve?
can you give an example and tell us what it would sound like?