Since there's a Github Issue on this topic, now there's also a blog post: https://blog.gradle.org/three-kotlin-versions-in-a-gradle-project

this is a good blog post. I wish it also touched on what it means for gradle plugins. These are gradle projects but they're special because they rely even more heavily on the Gradle runtime than other kinds of projects

Very cool article!

I have an empty build.gradle.kts for that reason

plugins {
    // Keep the embedded Kotlin JVM plugin on the included-build parent classpath so
    // `build-stat` can apply it without loading a second Kotlin plugin classpath
    // alongside the `kotlin-dsl` plugin used by `conventions`.
    embeddedKotlin("jvm") apply false
}

There's very little reason to use

embedded-kotlin

for KGP. What you want is almost always latest KGP with compat flags