A mix of iOS APIs and google maps taking advantage of them, but not really to do with WhatsApp.
When you copy an address in any app and open (Apple) Maps or Google Maps - and perhaps other mapping apps - they will present the option to search the address in your clipboard.
If you do this in a Apple Maps, next time you copy an address and go to multi tasking it will do what’s in your screenshot but for Apple Maps. Use the feature in Google Maps again to switch back.
That’s all I really know about this feature, someone else might know more