Didn't realize there was a demand for something like that, as this is the first time I have heard of this complaint. What is the issue? Even using a battery with 20% left after flying would power the Solo a very long time with the motors off, and transferring the logs from a day of flying would be pretty quick. Or, if you are on Android, just transfer them from the tablet/phone instead, while the batteries are charging.
I power my Solo from an old 12V wall wart when I'm doing development.
I added a switch and led to one of my break out boards as shown in the pix.
I'll probably put on the USB conn and a jumper for the OTG signal when I get the time.
Soloctrl sayd battery too low to fly, but then it's not gonna fly while on my bench. ;>)
Most of the important stuff is here: Future of Solo
If you have the Accessory bay USB connection, log downloads are very quick.
You will need a breakout board of some sort. Or some way of connection to the battery bay pins (not recommended)
The Battery connections that come out the Accessory bay connector are good enough to power the Solo for bench top NON MOTOR RUNNING operation. My old wall wart doesn't put out enough power to run the motors, and the controller thinks the voltage is too low to fly so it puts up a warning. neither of which matter fro bench top development.