Adding a comment here, because I was pulling my hair out and not finding anything on the Internet with how this can be done specifically I have Kasa HS230. I bought two of the version 1.0 kits. I was

Do you plan to release a four way smart switch product, or add functionality for two three way switch products to implement a four way solution?

Release a kasa four way smart switch product, or add functionality for two three way switch products to implement a four way solution.