>>107038565
>2/3 different voltages
>2 different types of transformer connections
>no standardized domestic sockets until recently (imagine 5 times of incompatible sockets)
>60 Hz in a region of 50 Hz and with high dependency of energy exchange (renewable energy), the Southern Cone's partially unified power grid (Brazil, Paraguay, Argentina, Uruguay) has a lot of frequency converter stations/HVDC line to balance power generation
In a sense it's similar to Japan but with worse safety.