By idea it can be possible, as software for remote control exist. But not sure how it works for focus.
In theory, it shouldn't be too hard to figure out how to do it as long as the communication isn't encrypted.
I haven't used this software, but it looks like it would do what is needed: https://freeusbanalyzer.com/
Run the software, plug the camera into the computer, load the Panasonic control app that can control the camera, and adjust focus through software. From that, you should be able to see the commands sent by the software to initialize the camera and to adjust focus.
With that, it should be pretty easy to make a raspberry pi zero controller with a couple of buttons and a small battery.
Otherwise, if you're willing to use EF lenses, you could use something like the Aputure DEC Lens Regain which lets you control the lens focus wirelessly.
@eatstoomuchjam Sounds great, i will definitly try this as soon as i have the time for it. Will keep you informed in case you are interested. I'm surprised that nobody else tried this before (at least i hadn't been able to find somebody writing about it)
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