There is a fix in the GitHub repo for Arduino https://github.com/m5stack/M5StickC/pull/52 .

Just for future references. The dual button module works fine using the 8 pines connector with a breadboard or directly with the grove connector. You just need to use the correct numbers in Arduino (I didn't test micropython).

You only can use G36 as input, everything else can work as input/output.

Thank you both for the help!. I bought the stickc yesterday and a few gpio grove modules. I was looking how the gpio ports work and the 8 pines port should be enough to connect a gpio module.

Hi, I'm new to the microcontrollers and boards. I would like to buy the m5stickc and some sensors but I don't know what grove modules are compatible with the m5stickc. If I understand correctly, the grove connector in the m5stick is only compatible with the i2c modules but I was wondering if would be possible to connect also the GPIO modules using the 8 pins extension connector and a breadboard. Is that possible?.