Too many variables. I have been flying over 54 years and am a senior AME (US)
ANR headsets have a certain frequency response that is optimum. So do digital hearing aids. My combination Bose X series and top of the line Phonak with optional remote control work well on cetain settings which takes some experimenting to find the right combination. It also depends on the environment; I fly mostly piston twins, warbirds (T-6) there dosen't seem to be as much problem in light jets, biz jets, etc.. My hearing loss (sensori-neural) is to high and mid tones and moderatally severe. Less severe loss can be corrected with just a headset and no hearing aids, just turn up the volume. Air crew have differing problems depending on company protocol and how they communicated with each other.
Your best bet is to find a well trained audiologist (Audiology degree & MS or PhD) take the specs of your headset with you and have him prescribe an appropriate hearing aid. This will only work if the audiologist dispenses more than one brand of aid as each aid has differing frequency response.