Have you told Intellij about the project dependencies? I mean, it sounds like either that class does not exist or you haven't linked the projects so that Intellij is using the build of one project ...

IntelliJ IDEA can now perform a number of actions inside WSL 2, including detecting detect JDK installations, installing JDKs, and compiling and running projects using the IntelliJ IDEA build system.

If developers want to compile a project to the K2 compiler, they will need to specify this in build settings. JetBrains describes K2 as a high-performance compiler for the Kotlin language.