1 Dashboard RGBW dimmer - multiple RGBW lights

[boydde3de]

Dear all,

I'm confident that this question has been either asked before, or has a simple solution which I just can't find and thus offer my apologies.
I just started using Domoticz and I'm trying to control two RGBW led bulbs (Aeotec).
I managed to make a dummy switch which I made a slave of both lights. When I change the colours or state on the dummy switch it will be interpreted by both lights correctly in Domoticz. However, the physical state of the lights don't change.
The log shows that even though Domoticz makes changes on the dashboard (on/off, colour), no signal is sent to the light themselves.
This question regards multiple cases for the future.

How to control multiple devices through 1 switch that has more functions than on/off.
Yes I know scenes. But I would like to change the colour of all lights simultaneously on my phone through the dashboard.

Hardware:
Rasperry PI 3b
Aeotec Zstick gen5
Aeotech RGBW LED bulb x2

Software:
Domoticz stable v3.8153
Newest Raspbian Lite software

Thanks in forward,
Boydde3de