I ended up using this ZHA - Inovelli Blue Series 2-1 Switch LED Notification Script. Once that is set up as a script you can do something like this:
action: script.inovelli_notification
data:
led: "{{ some variable here }}"
effect: "{{ effect }}"
duration: 255
color: 150
level: 50
switch: "{{ some variable here }}"
Not sure if this advice applies to other types of devices/actions, but perhaps you can see what the script is doing and make your own solution based on that.