Thanks. I guess you went the smarter route looking for a solution :)
I was curious myself... that's beyond what I would expect in an emulator
Answering my own question (partially): some Apple II emulators seem to have that functionality built-in, for instance VirtualII that has "Epson FX-80 and Imagewriter II emulation". Now I wonder what emulator they are using with WASM. They are essentially loading a file called "cyanide.wasm" but I could not find an emulator with that name.