I bought the Aqara hub M2 and Aqara hub E1. Because I'm determined to install some of their smart light switch. My home uses eero pro 6e with 3 routers. Because the Aqara E1 only supports 2.4Ghz, so I use the troubleshooting option in eero app to temporarily turn off 5ghz (I also turned on legacy mode, turned off WPA3 etc.). But I still can't get the Aqara E1 connect to my wifi, the error is always "network credential generation failed" after I scan or input the Apple Home Kit code. At that time I already installed Aqara switch, so there's no way back (uninstall switch is harder). I tried Aqara hub M2, at first couple of tries I still can't manage to get it work. But then I found using the bluetooth mode to set wifi password in that flow get the Aqara M2 to work with my eero (you don't even need turn off 5ghz or turn on legacy mode). Also the Aqara M2 has the wired option which always works more reliably. So eventually I kept the Aqara M2 (which I'm not very satisfied too, but that works). This Aqara E1 is useless when I'm on my eero network setup.
Hope this save you some time and patience when you are also using eero.