This is a proof of concept that is only available on their subscription service simply because the website version of 1Password is tied to the subscription serv

This is a proof of concept that is only available on their subscription service simply because the website version of 1Password is tied to the subscription service. If you read the article they said they'd be adding it to Watchtower, which is the feature built into the native client where it tells you about compromised sites. So once they add it to Watchtower, you'll be able to use it without the subscription service.