I'm not quite sure what you want to do, but it might well be easier to use an Espruino Pico and the Arduino Adaptor for it.
But if you're just playing around, feel free - just don't expect it to be easy :) You'll definitely have to do your own builds, and getting USB working is often a complete pain.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I'm not quite sure what you want to do, but it might well be easier to use an Espruino Pico and the Arduino Adaptor for it.
But if you're just playing around, feel free - just don't expect it to be easy :) You'll definitely have to do your own builds, and getting USB working is often a complete pain.