Been looking for a project example where someone is using a slave micro communicating to a master via a remote I2C transceiver chip.
This inexpensive slave could be used to act like an I/O expander for remote serial, A/D and digital I/O far cheaper than having to buy multiple I2C chips to do that function.
My remote board has to be more than 30 meters away, and may have quite a few sensors. I could buy several I2C chips and hook them to the remote I2C transceiver I suppose...
I2C remote transceiver chip is Texas Instruments P82B715
The datasheet says "approximately 50 meters" but in reality this is more 10 to 15 meters. Your experience may vary and it may depend on the used cable but I still think I2C is the wrong interface choice for such distances.
BTW: the P82B715 is not a remove transceiver chip, you need a chip on both ends (remote and local) of the long wire. It's a bus extender.
Replace your Nanos with NodeMCU and you have WiFi connectivity at about nothing extra. So cheaper than your I2C extender, even before you start looking into what kind of wire you'd need to transmit I2C in a noisy environment over 30 meters. That long wire is a fantastic antenna, picking up lots of noise, messing up your signal. You're probably going to need a well shielded cable.
This is also why RS485 and similar long-distance protocols use balanced, current based signals. Much more immune to noise. Your P82B715 is likely to propagate the noise together with the signal, as what it does is buffering.