Per their website, all Stratus transponders are ADS-B Out only, including the ESG. I don't see an option to purchase an ESG with AHRS, so it must be coming from one of their portable systems. Perhaps it's buried deeper in their website but like you said, they don't make it easy to find. If I'm correct, then you'll have to buy an additional piece of hardware to get ADS-B in, and if you buy one of theirs, it may well be locked into talking only to Foreflight. FF, Appareo, and Sporty's are pretty much married to each other and that's been their modus operandi lately: locking a user into using only THEIR hardware and software. Their most recent example of this practice is the Scout.