I had a thought today. We all know that's dangerous enough as-is, but hear me out anyway. Some ground info needs to be established. If I'm off on any of this, please LMK so we can get on the right track.
For a semi-acoustic, there needs to be a solid block for the pups & bridge to mount on. This is because of feedback. To the best of my knowledge, this applies to chambered solid-bodies as well.
Acoustics have very thin wood which vibrates, this amplifying & shaping the sound. It requires bracing due to the lack of thickness.
Chambered electrics have thicker sides & tops, and therefore do not require bracing. From a topic I posted some months ago, the thinnedt you should go with a chambered electric is about 1/4". Beyond that and the wood might be too thin.
So...
Let's take a solid body electric, and chamber it. Nothing new. Let's only leave a small block inside at the neck pocket, just big enough to have a neck pup as well. We'll also leave a small block for the bridge. EVERYTHING else is hollowed out to aboy 1/4"-3/8". We'll have a 1/4" cap, or maybe a 1/2" that has been carved. Instead of f-holes, let's put a big round acoustic hole between the neck pup & the bridge.
How would you predict this would sound acoustically? Clearly it wouldn't be anywhere as loud as a real acoustic, but with some heavier gauge strings, it could be OK. At minimum, it'd be a pretty sweet jazz guitar.
Let's take it a little further. Let's say it's 2 1/2" thick. That'd leave you just under 2" for the sound box. Then let's put in a true acoustic pup system. NOW what happens when it's plugged in?
Since we've gone that far, let's NOT leave the solid block under the bridge. Instead, let's put in a TOM bridge mounted on a piece of rosewood/ebony like an archtop. NOW what happens?