This is really cool! I see you’ve got screenshot of it running on Android, could this ever also work on iOS? I tried in iOS on Chrome, but I just see “WebUSB not supported. Use Chrome, Edge, or Brave.”.
I am not sure what are you trying to say with this comment. AFAIK there is not a single browser on iOS that is not webkit. Even in EU all browsers are reskinned safari.
Also even if somebody build browser engine for alt store then the support of WebUSB (which for sure needs support from OS) would require Apple involvement.
You will have to wait until the WebUSB support lands in Safari.