Apple is researching ways that other devices such as straps or even AirPods, can charge an Apple Vision Pro while in use.
Or it can’t at present. A newly-revealed patent application called “HMD with Charging Device” proposes that an Apple Vision Pro could be “charged using a wearable electronic device.” While the patent application is typically vague about that wearable device, it is clear that it would “magnetically connect… to transfer power.”
While the text is as consciously unspecific as all patent applications are, the drawings with it are much less so. All illustrations that show any device being attached to the Apple Vision Pro appear to be showing AirPods.