I know twisted pairs are important for differential signals, which I2C is not. I also know I2C is not intended to be used over long wires. However, I made a design where I need to use a cable to connect two devices over I2C. The expected length is 0.2m to 0.5m. I am shopping for wires now and there is a nice 4-wire cable that fits the specs and a very similar cable with wires twisted in 2 pairs. I wonder, does I2C communication benefit from a twisted pair? Or might it hurt it perhaps? Or should I just choose the cable of the better color?
If you follow a proper EMI concept, then nothing speaks against connecting two devices over I2C.
Yes, you should use a twisted pair cable, as this is the weapon of choice against inductive coupling. If you use a shielded cable, you can suppress capacitive coupling, too (You must connect both ends of the shield, but beware of ground loops).
You can do even better if you isolate the I2C transceiver at one end.