Babylon’s WebXR is not a magic tool. It is a simpler interface to the native WebXR API. it is a view definition, wrapped with some other APIs and other goodies to simplify the process of XR integration.
Anything you can do with Babylon will work with WebXR. you might have a different user interaction, and you might need to develop some UI elements or processes yourself, but of course - anything that is possible with native WebXR and native WebGL can be done using BabylonJS (and other way around, i must say. it will just take a LOT longer )