This is what my dual NES adapter could look like in the end - a USB socket at one end, and two NES sockets at the other.
Designing this while trying to keep in mind a consistent design language for other future adapters is hard. I *think* this is large and general enough that I can modify it for other sizes without hugely changing the design language (and to be fair I've picked the biggest, most complex one to try to start with).
