Do you really mean the IKEA Trådfri Signal Repeater (a dedicated Zigbee Router device) product?
Again see → Zigbee networks: how to guide for avoiding interference and optimize for getting better range + coverage
You can not use IKEA DIRIGERA Hub in combination with the ZHA integration, nor with Zigbee2MQTT or any other Zigbee gateway. And the IKEA DIRIGERA Hub can only control IKEA branded devices.
To clarify; IKEA DIRIGERA Hub (which replaces the older IKEA Trådfri Gateway) is Zigbee gateway, not a Zigbee Router device that can be used as a Zigbee repeater, (meaning that the IKEA DIRIGERA Hub is a Zigbee gateway/bridge/hub/controller that has its own built-in Zigbee). Each Zigbee gateway will have its own isolated network (e.i. private area network.
You can not connect a Zigbee device to two Zigbee gateways, and only Zigbee devices on the same Zigbee gateway/network can communicate with each other. Two Zigbee gateways/networks also have no interactions with each other at the Zigbee level at all. So if you have two Zigbee gateways then they are not aware of each other in any way, thus all integrations have to be done at the application level (i.e. in Home Asssistant’s automations and scripts or such).