Another idea. If all psio is based on FPGA controller, why not make a simple network microcontroller too (something on ATMega?) and write a simple clinet to seti it up and run? It would emulate second pad for example and games such 2 players and multitap ones could be awesome to play. Of course there is no any thinking about chat-in-game or something like that.
But it could be fun i think

It could work just like that:
-after start of the program that handles small networking hardware the 2 port of joypad input will be blocked
-client is starting. All internet things are going into setup routing IP etc... (i dont know much about this)
-Program wants to insert the disc and we can go into "room".
-Create, wait, play
-here is the point that if any player will unconnect/power off the console that mean offline game ofc and unblock the 2 port
Simple like kaillera but in normal console and self-sufficient. I know that there is no special need for it but imagine psx with network support!

It would be just PSX v1.5 haha

Would it be possible or is this just stupid dream ? We all know that there's only 33 MHz and 2MBs of RAM :/.