Even wireless cameras need shore power if you expect to have a 24/7 live feed that you can later review.
So you may not need to run coax from the camera to the DVR anymore, but you still need to run a low-voltage power wire to each camera.
There are motion-triggered cameras that are battery/solar powered, but they only record when activated.
We have some Blink Cameras as. They go on sale several times a year. They do not need a cable to them and the batteries last a long time. But they now need a paid subscription if you were not grandfathered in previously. You also need an add on device if you want the video recorded locally, which is why we do not prefer them.
https://www.amazon.com/Blink-Outdoor-Wireless-Security-Camera-Add-on/dp/B086DKMSSM