In the end I didnt need to use product flavours.
For the library project I added the following:
android {
sourceSets {
main {
jniLibs.srcDirs = ['libs']
}
}
}
The libs folder had a folder inside called “armeabi-v7a” and as this is my only target it worked a treat.
The ndk files (.so) are propagated into the android project that is using the android library project.