I guess you've looked in to CROS and biCROS hearing aids?

http://phb.secondsensehearing.com/content/hearing-aid-review...

I'm pretty sure you can get an in-the-ear version of these, which would mean you could wear and almost invisible aid in your other ear.

https://www.phonak.com/uk/en/hearing-aids/phonak-cros-II.htm...