I confirm scenes work in english, as other commands do:
For example:
"Turn on lights" turns on all the connected lights
"Turn off lights" turns off all lights
"Dim lights" dims all lights a bit (this is nice, does not always work)
You can also target a specific light by its name:
"Turn on Kitchen1" turns on the light named "Kitchen1"
or also "Turn Kitchen1 green" makes it green
In italian Siri has become a mess, for example, if I press home button asking for Siri, and then say nothing, it understands "Che".
It looks like the italian Siri is stuck in some sort of a mixed up reduced dictionary composed of a few italian words, some Hue/Homekit words like "Home", and the titles of the Hue app scene pages. If, for example, you have a scene page titled like "Bedroom" that's a word it understands.
Also I discovered that continuing to stress Siri (by tapping the waveform) to recognise italian correctly by repeating the same question two, three, or more times in a few seconds sometimes it gets the correct italian sentence (for example, "Accendi le luci") and performs the command.
Switching language to "Italian (Switzerland)" seems to be working for a few seconds, then the language confusion comes back.
Since voice recognition is messed up I tried typing in some command (just tap "tocca per modificare" the phrase Siri recognised).
For example "Accendi le luci" and "Spegni le luci" do work.
Also a command that should be working with italian Siri to choose a scene should be "Imposta scena Forest" (Set scene Foresta), but it tells it can't find such a scene even if it exists.
Hopefully it will be fixed soon, I am sure Apple and Philips are already aware of the issues and working towards a resolution.