I hear you, and had to do the same for a while. Eventually your brain migrates over and it becomes second nature. The ability to copy Java code and paste it as Kotlin helps tremendously, especially in the beginning.

> I have, it's a nice language but I didn't like the mental tax of translating Java code to Kotlin in my head whenever I had to read up on how to do something

You can always let your IDE also do some of the work, at least for a quick reference: https://www.jetbrains.com/help/idea/get-started-with-kotlin....

Of course, when you get into slightly different idioms or design pattern implementations, things might require a bit more mental effort and manual work.