There are no <uses-feature>
elements or <uses-configuration>
elements that allow you to filter on the existence of off-screen affordances for HOME and back, at least that I can see.
Hence, other than manually identifying devices that you want to support, and manually limiting distribution to them in the Play Store, I do not see another way to handle your request.
The point behind something like immersive mode is for it to be used on all devices, albeit with differing effects depending on device characteristics.