You could make a series of automation rules that perform this, it’d just take some time to setup… for eg if both a + b >= 300, if a >= 250 + b >=350, if a >= 350 + b >= 250… and so on.
You could write a little app that does this, and creates a virtual device that always provides the average. Then you could use that in Rule Machine just like any other sensor.
I’d need some guidance on how to do this, i’m not a coder by any means. However, I think of myself as a pretty good student!
In this case it’s just the lux of two different fibaro sensors that I’m looking for an average of. It’s not SUPER important so if it’s a bother please don’t spend much time guiding me. I’m just trying to duplicate some of the conditions I was previously using in webCoRE.