I would not try to convert one of these micro-excavators into a remote piloted unit, for a variety of reasons.
First, these machines are extremely unstable. You can find videos of people getting thrown off these micro-machines or laying them on their side. While removing the human operator would lower the center of gravity slightly, I would not expect that to be enough to change the equation.
Second, operating the machine involves sensing force feedback from the machine as it encounters resistance. I am not sure how that feedback could be translated to a remote operator. The operator seat also gives the best vantage point for seeing where you're driving, swinging the arm, and using the bucket/attachment.
Sure, you might be able to upgrade the controls to use solenoids for remote piloting, sensors on the hydraulics to send force feedback to your controller joysticks, and add a FPV camera system and AR headset that gives roughly the same visual perspective. Those extra systems would likely double or triple the cost of the machine. Even then, I think those solutions would be grossly inferior to the sensory feedback (and overall visceral experience) that you get from sitting on the machine and operating it directly.
For perspective, I spent less than $6K for a brand new machine, a pallet full of attachments (quick connect, two augers, several buckets, rake, and grapple), as well as a variety of performance and convenience upgrades (oil cooler/filter, swing motor cushion valve block, hydraulic thumb, auxiliary valves, and much more). At the end of the day, that is significantly less than the medical costs involved with repairing an intestinal hernia or ruptured disc.