Wiring 3 Way Switch With 12/2. Web if one connects the hot to the first common, the neutral goes up to the light on a 12/2, and the black conductor in that 12/2 isn't used. The travelers go to the second 3.
There are many on the market. Web if one connects the hot to the first common, the neutral goes up to the light on a 12/2, and the black conductor in that 12/2 isn't used. 3 best way would be to use a 'smart' switch of some sort.