Database routing for multiple environments

I'm looking into the new Database Routing feature. We have multiple environments (i.e., dev, demo, prod), and they all have the same database schema. We want to use the same dashboards across all of them.

We're using static embedding to add dashboards to our site, so there are no user attributes yet.

Is this feature suitable in my case?

Metabase version: v1.55.6.2

Yup! Perfectly fine

Could you please guide me how to do it? The main question is how can I add a user attribute when using static embedding?