Personally I currently recommend CC2652P based dongles with external antenna, such as the either the Ethernet based ones from either Tube and ZigStar, or better yet is to use a USB based one with a very long extension cable, like , or ITead’s “Sonoff Zigbee 3.0 USB Dongle Plus” (model “ZBDongle-P”) based on Texas Instruments CC2652P +20dBm radio SoC/MCU.
Regardless of Zigbee Coordinator be sure to read and follow this → Guide for Zigbee interference avoidance and network range/coverage optimization
Note that the ITEAD Sonoff ZBBridge is not recommended as a Zigbee Coordinator for ZHA integration or Zigbee2MQTT for the same reason that no WiFi-based Serial-to-IP bridges are not recommended, as the serial protocol does not have enough fault-tolerance to handle packet loss or latency delays that can normally occur over WiFi connections, and therefore both ZHA integration and Zigbee2MQTT have warnings against using WiFi-based Serial-to-IP bridges
https://www.zigbee2mqtt.io/advanced/remote-adapter/connect_to_a_remote_sonoff_zbbridge.html
https://www.zigbee2mqtt.io/advanced/remote-adapter/connect_to_a_remote_adapter.html