Do Qiscus In-App Chat SDK for Android Support Kotlin Language?

Yes, Kotlin is designed with Java Interoperability in mind. Existing Java code can be called from Kotlin in a natural way, and Kotlin code can be used from Java rather smoothly as well (kotlin).

Qiscus Chat SDK is built with Java language, if you already have Kotlin in your project you can copy-paste Qiscus Chat SDK Code into Kotlin language by following this documentation https://developer.android.com/studio/projects/add-kotlin#convert-to-kotlin-code