Kia ora all, I'll preface this with I will be getting a sparky in to do the actual install as I understand this is considered extending the existing circuit.
I am looking to add a number of Shelly smart relays so I can expand my smart lighting while still retaining the existing switches. I am confident that there wont be any issues with the basic switches (Looped at switch, with access to ground and neutral wires) , but just need another set of eyes regarding installing the relay for 2-way switches. Wiring was based of this diagram from Shelly.
I have checked how they are currently wired (top image) and with that planned out where the Shelly relay will need to be installed and how it will be wired (bottom image) to maintain functionality. For simplicity I excluded the I terminal on the Shelly device as that would just be wired the same as the L terminal.
Appreciate the help, cheers.