Is there an Apple AudioUnit plugin that provides a different EQ for each channel?

I'm using SoundSource to allow myself finer control about my audio, including EQs and different output devices for different apps.

I also discovered that I can add Apple's preinstalled AU plugins to the mixer:

I would like to know if there is any AU plugin on the market that provides an individual EQ for each channel (left and right, stereo) that I can install and use in SoundSource, please?

Solution 1:

I found a multi-channel AU/VST plugin which SoundSource can use.
I've no idea how good or flexible it is, so give it a try. It claims to be multi-channel but I can't tell from the description whether these can be configured truly independently.
Voxengo Overtone GEQ
The 'problem' with EQing L/R separately - & why it's less likely to crop up in 'pro' audio editors - is that EQ changes phase*; so changing phase on each side of a stereo image can produce slightly odd results.

I answered a question on here once, a while back, on how to do something similar, but it was using Audio Hijack [SoundSource's older brother] & contains it own plugins which can split left & right [they're not installed as AUs, they're definitely internal to the app… I tried before;)
There's another answer underneath using Soundflower & AU Lab, but I stopped using those years ago & don't know if they still work on newer OSes.

*It doesn't always & can be partially avoided, but that's an entire university dissertation;)