Hello, I am looking for device to setup a wifi roaming. Now I have a Hap ac2 and I want to buy hap ax lite to setup wifi between two floors on my boulding. Can i use hap ax lite or better chose is secound hap ac2 to wifi access point? Of course hap ac2 with wifi wave2

Not so sure, but ax lite should work. Beware that is a 2.4ghz-only device.

Yes I know but I dont must use 5ghz