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Details of device selection for hubs can be found here: https://developer.amazon.com/en-US/docs/alexa/smarthome/wwa-console.html#register-your-product
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Regarding "Works with Alexa Requirements for a Smart Home Skill" problem
What is the process of obtaining the Amazon Alexa authentication ？
WWA Certification - with a custom skill
Device status not change with unreachable
How can I get a "Works with Amazon Alexa " credentials?