Could not find any option. Battery powered means no webserver which means no http or rtsp access/stream - and therefore all the options to integrate into HA (like Reolink IP Camera, MotionEye, ONVIF, Generic Camera, …) are not available.
Too bad because it’s basically great hardware, even better when solar charged. But without capable of being integrated to HA… useless to me, unfortunately.
Update:
Reolink Argus 2 Camera Integrated to HA - #5 by cmgreenman or Reolink Argus 2 Camera Integrated to HA - #14 by axl84 seem to be the only options. Not really straightforward.