You don't say what core you're compiling with, your wiring diagram has no power source, neither of your ATtiny's have either their Vcc or GND pins hooked up, it appears you want to use PB1 (pin 6) as an output but you have nothing hooked up to it, you have no connections on SDA (pin 5) or SCL (pin 7). And at that point I simply stopped looking.
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