@casitamaguire 

It would work, but not seamlessly, you need either a OneMesh network (link) or a Deco mesh network. The RE305 hardware versoin 3 is OneMesh compatible, but you also need a OneMesh router (link).

So with the current equipment you have, you can set up both extenders and make them the same network name, but you will likely see network drops or bad signal strength. Reason being the bad strength would come from devices not moving over and staying connected to the further device. The network drops would happen from the device moving over form one RE305 to the other, no different then manually connecting to a new Wi-Fi network which the connection drops.

Would be best to have both RE305s with the same wireless password, but different network names to avoid issues.