I wrote a blog post on how to handle the Lombok @Builder annotation when converting a Java project to Kotlin:
https://code.gematik.de/tech/2023/01/11/no-builder-in-kotlin.html
The target audience is less people who are already very familiar with Kotlin but their Java dev colleagues, who only had a 3-day Kotlin training, because not all patterns have a 1-to-1 mapping to Kotlin.