Zigbee Coordinator adapter are presented as a standard serial port so need somehow connect that serial communcation to either the ZHA integration inside Home Assistant or Zigbee2MQTT, (with Zigbee2MQTT again being a stand-alone Zigbee gateway application working like an exteral hub).
Zigbee Coordinator USB adapter obviously require a USB-interface, so the norm is to direct- attach it directly via a long USB extension cable to a computer to its OS or pass-though it to a virtual machine.
While not primarily recommended as a more expensive solution you can as an alternative to direct- attach via USB instead make or buy a network-attached Zigbee Coordinator adapter which uses a “ser2net” style serial stream server can tunnel the serial communication over TCP via “socat”. See example:
https://www.tubeszb.com/ and https://github.com/tube0013/tube_gateways
or
https://zig-star.com/projects/zigbee-gw-lan/ and https://github.com/mercenaruss/zigstar_gateways
Note however that the serial protocol that Zigbee Coordinator adapters use is not designed to be robust or fault-tolerant as they expect a direct-attached connection, this is a bad idea to try to tunnel such serial communication over Wi-Fi, but over a wired Ethernet LAN is usually stable enough.
However, long-term it should better to run Home Assistant on a Raspberry Pi or similar computer with a direct-attached Zigbee Coordinator USB adapter as that will be the most stable option. See example:
UPDATED! The announced TI CC2652P based “Sonoff Zigbee 3.0 USB Dongle Plus” from ITead, later renamed to “ZBDongle-P”, has been released and looks to be great value for a premium hardware package sold for a low price. It is based on Texas Instruments CC2652P radio chip and this “ZBDongle-P” variant is to be sold side-by-side as an alternative to their new “ZBDongle-E” variant that is instead based on Silicon Labs EFR32MG21 radio SoC chip, and while both practically have the same specifications o…