I solved the problem:

project.dependencies.add("${variant.name}CompileOnly", project.files(
        processRes.outputs.files.find {
            it.path.endsWith("${variant.name}/R.jar")
        })
)

So i guess there must be some mechanism behind

compileOnly

(just change

appRJarConfName

to

"${variant.name}CompileOnly"

and it works fine). Thread in Slack Conversation