pck1 imports pck2 which does import bluebird.
See https://github.com/Raigen/babel7-tmp for Babel 7 version.
npm install
$ npm start
> babel6-sample@1.0.0 start C:\Users\foellerich\Git\babel6-tmp
> lerna exec --scope pck1 -- npm start
lerna info version 2.7.0
lerna info scope pck1
> pck1@1.0.0 start C:\Users\foellerich\Git\babel6-tmp\packages\pck1
> babel-node index.js
done