Added i2c pcf8574 to the mix. I did not want to run 12 connectors over but i also wanted to keep the software simple so we added one for each side. Unfortunatelty i cant find an affordable ic with both analog and digital multiplexer so the joycon still has to be run accross. 6 total accross the phone still beats the old design running 8.
Each multiplexer will have 3*3 matrix buttons, L3/R3 and and led indicator for a total of 8 pins.
[maave] is adding my s9+ to the case designs while help out with the schematics.