Can pick Colors with Google Assistant, but not Amazon Echo (Alexa)

I have a device defined:

Color		OfficeLEDColor	"Office Accent"  (gOffice, gPersist)  ["Switchable"] 

and am using both Google Assistant and Echo via the Hue emulation.
Google supports colors – “Alexa, set Office Accent color blue”, bit Alexa only seems to support on/off/dim commands. In the Alexa app, it states “Color Capabilities: none”.
I’ve tried both “Switchable” and “Lighting” as the tag, and in either case I seem to get the same result.

The device is a home-built ESP8266 controlling addressable LEDs, the following rule drives it:

rule	"Office Color change"
	Item OfficeLEDColor received update
	var hsbValue = OfficeLEDColor.state as HSBType
	var   redValue = ( * 255) / 100
	var   greenValue = ( * 255) / 100
	var   blueValue = ( * 255) / 100

	var String formattedString = String::format("color:%03d,%03d,%03d", redValue, greenValue, blueValue)
	logInfo("<<< Setting OfficeLEDColor Color to >>>", formattedString);
	publish("mqtt87", "/ledlights/office", formattedString)

I’d really like to get this working with both platforms, as we have a mixture of devices in different rooms.

No one answered? Just turned this on as Alexa Skill no longer getting updates from MyOpenhab reliably and stumped that color isnt supported under Hue Emulation

Have you tried the Color or Colour tag?

It is my understanding that…

Lighting means a simple single channel dimmer

Switchable means a simple ON or OFF state.

I’d love to know how to get colour picking working with Google Assistant

Yes. Looking at the Hue Emulation code - not seeing where the color tags are translating to passing on anything other than dimmable light.