Metageeks, the manufacturer of WLAN Zigbee diagnose sticks has released a very good article over the coexistence of both of them. Read on here:
https://www.metageek.com/training/resources/zigbee-wifi-coexistence.html?utm_source=MetaGeek+Customers&utm_campaign=299f8722cd-WOM+-+Training+%233+-+set+up+different+router&utm_medium=email&utm_term=0_e687c57690-299f8722cd-33093625&mc_cid=299f8722cd&mc_eid=12f3c8c804