Yes is quite simple until packets are not received in order that are transmitted and other packets are not received at all.
Maybe a Zigbee wireless serial transceiver module is more stable? I don’t know. I just found this https://item.taobao.com/item.htm?spm=a230r.22.214.171.124e064cc2xT5p6D&id=546508373498&ns=1&abbucket=14#detail
It seems easier than other wireless communication modes. And it just costs about $4.7
There are probably a bunch of better ways you could do communication if you were redesigning the Arduboy or making hardware mods but I was trying to see what could be done with two standard Arduboys without needing to change the hardware.
Got it. I made new PCBs in which through hole LED has been used. It’s different from what is using in Arduboy. Maybe I’ll have a try to see if it works.