I am looking for multiplayer connection ext too.
And as @kwx mentioned it seems no any one can work by now.
I think it would actually be easier if it were possible to make this a two-player game, for example using the cable connection for PyGamer, since then there’s no need to write enemy AI code. However, last I checked this wasn’t working: Hardware Multiplayer (game) - #39 by jwunderl
And I tried microsoft/pxt-jacdac also, but I didn’t found any device like Arcade. There’s almost all periphery devices, no other console device, execpt micro:bit V2.
Jacdac connector/cable has change to a dedicate form, I am afraid that simple audio cable are not support any more. Hope I am wrong about it.
As a alternative way, I maybe use spi/uart/i2c, or wireless card of Meowbit for connecting devices, at the time my project need it.