Shelly Dimmer 2 with 3-way switch (again) but with out of phase live

  • I know this topic has been talked about endlessly, but Im working on wiring a dimmer2 at the last position of a standard 3-way switch setup.

    The final 3-way switch is in a 4-gang box, so I figured I could steal a live from another switch, however, it turns out the live of every other switch in the box is on another (out of phase) circuit.

    Is there anything I can do here?

    I noticed there is a diagram where I can use neutral as the switch signal, can I hook the first switch's common to neutral in the 3-way circuit, the use the live from the other box?

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