I believe there are two ways to integrate smartthings with alexa. using ifttt gives control of single switches but does not require individual authorization of devices. Other method gives ability to group the switches but requires individual authorization. Can I do both to take advantage of groups when I need but be able to individual switches through ifttt?
The best way is to just use the smartthings Alexa app. It allows you to do both single switches and groups.
There is now an option in the smartapp to say “Allow Alexa to access all devices” instead of authorizing individually.
You will need to say “Alexa, discover new devices” if you add a new device.