Currently the only ways to modify an HDR curve is manually drag the points or to modify the XML file of the work unit directly. This feels pretty dangerous to the health of the project, very slow, and very clunky. Adding some functions to Waapi where we could access the curve data of an HDR curve and apply it to other objects would be ideal. Ideally there are some options to either scale or truncate/extend the curve on files of mismatched lengths.
The response from AK on a similar topic asking about HDR curve copy/pasting:
https://www.audiokinetic.com/qa/10200/paste-envelopes-points-sound-source-another-source-editor?show=10200#q10200