I think the issue with aviation headsets is not significantly different that regular noise cancelling hearing aids. Obviously the issue is feedback. I have found that I can simply turn down the volume and make it work. However, I don’t do it often and I am sure turning down the volume is not the best solution.
Not sure what your ear mold is, but it would help if you have very small vents. There is also the alternative in modern hearing aids to create another program with more aggressive feedback control and use that channel when you use the headset. When you get new hearing aids, take your headset to the fitter and they can tune a channel to reduce feedback when you wear the headset,
One of the respondents suggested posting your audiogram. Good idea.