I have had decent experiences with TiLP on linux. According to their website, it “can handle any TI calculator (from TI73 to V200) with any link cable.”. Their website also explicitly states support for the NSpire and NSpire-CAS, but the NSpire CX II isn’t mentioned. It might be worth a shot?
If it doesn’t work, the easiest solution would probably be a windows VM with USB-passtrough (which wine doesn’t support as far as I know). You could then use the webapp I linked earlier.