Hello Herschell,
At the moment, it's not possible to copy and paste envelopes directly in the Wwise Authoring, however, it is possible to copy and paste the envelopes in Work Units.
Try this:
- Go to SFX > HDR tab > Enable Envelope.
- Open Source Editor and make a custom curve.
- Right-click SFX > Open Containing Folder > NameOfYourWorkUnit.wwu
- Open up the file with a text editor (e.g. Visual Studio Code)
- Copy the SFX's <PropertyCurveList> ... </PropertyCurveList> section.
- Go to Work Unit of the other SFX.
- Paste in the code, just below <AudioFile>NameOfSFX.wav</AudioFile>
- Reload Wwise.
If you pasted the envelope into an SFX that is not the same length as the first one, you will get the following error...
"The duration of the HDR envelope curve does not match the duration of the source audio file. Repairing the source will adjust the curve to fit the new duration."
... but just click the warning icon and the curve will be repaired.