I doubt very many people will want to go to that much trouble
I just gave this Airfoil version of stereo a go with 2 homepods and it works really well.
I've been using a single homepod for a week. I had one at home and one at work. Now I finally took the one at work home and got this Airfoil thing going.
I have to say homepods in stereo is MUCH better than a single homepod (as good as a single homepod may be). So I won't be going back to just the single homepod again. From now on it is stereo for me - with or without apple's update. Thanks Airfoil!!!
(And if you want to really be blown away by stereo try Verdi's Requiem: III Tuba Mirum. I used this to test it out and Airfoil passed with flying colors!)
Instructions on how to use Airfoil for stereo homepods.
If you don't want to take 10 minutes watching the video I posted earlier and want to quickly set stereo up with Airfoil here are some instructions.
Disclaimer: I'm not here to advertise for Airfoil. Furthermore this use may be temporary since an update from apple is coming which will enable stereo. (On the other hand these guys seriously deserve money. I had no hesitation in paying them. And if you want stereo now and don't want to wait for apple to get their act together with their updates then you shouldn't either).
1. Download AirFoil
from Rogue Amoeba’s website. AirFoil is a paid application at $29 per user.
2. Once you have AirFoil downloaded, copy it to your Application folder.
3. Open it and ensure that all of your AirPlay-enabled devices appear.
4. Choose your audio source. Easiest way is to choose System Audio. Then all sounds from the mac will play. But if you are a bit fussy about mouse clicks not coming through for example you can select specific apps instead which will exclude such noises.
5. Go to your Applications folder on macOS and find the AirFoil app. Right click on that file and choose “Duplicate.” This makes another copy of Airfoil called Airfoil copy.
6. Open Airfoil copy. It will open right over the Airfoil window. Move it away from it.
7. In AirFoil, choose the HomePod that’s on the right side of your configuration. Click the equalizer icon along the top and drag the “Balance” slider all the way to the right side. This will play only the right channel through that HomePod.
8. In AirFoil copy, choose the HomePod that’s on the left side of your configuration. Click the equalizer icon along the top and drag the “Balance” slider all the way to the left side. This will play only the left channel through that HomePod.
So here is my setup: (Bedroom is the right homepod and Bedroom (2) is the left homepod)
Main windows: (unfortunately the apps both call themselves Airfoil, not Airfoil and Airfoil copy so it can be a bit tricky to see which one is which - not hard though once you get used to it.)
Left and Right Balances: