Composite Build: combine modules from multimodule projects

In my current environment we have fairly large multi-module project setups, where not every developer needs every module in his workspace. Also there is a need to be able to combine modules from separate projects in one workspace. This was looking like the perfect use case for composite builds until we tried them…

While importing multi-module-builds as a whole works:

settings.gradle:

includeBuild 'multi-1'
includeBuild 'multi-2'

we had some work to do to be able to adress individual modules:

includeBuild 'multi-1/module-1'

this was mainly due to configurations that where made in the parent build.gradle, but nothing we did not see coming. But now we are stuck with project-dependencies.

multi-1/module-2/build.gradle

plugins {
    id 'java'
}
group 'com.multi'
println "configuring $project.group:$project.name:$project.version"

dependencies {
    implementation project(':module-1')
}

even if we try to import the referenced module in the build:
settings.gradle

includeBuild 'multi-1/module-1'
includeBuild 'multi-1/module-2'

gradle keeps saying:

A problem occurred evaluating project ':module-2'.
> Project with path ':module-1' could not be found in project ':module-2'.

we tried to use dependencySubstitution but no setup did make any difference.

Dropping the whole multi-module-build is also killing any eclipse-wtp support and therefor not an option. Also all subproject configuration/listing/task-execution is very limited in composite builds.

Any help would be apreciated.