Here are my experiments with passport-js with local authentication and with es6 based server setup.
The serialize and deserialize of passport-js is statically coded in. But you can get the same to be working as per any normal way of deserializing that you like.
This also contains a very simple implementation of mongodb based db class in ES6 ways of implementation. Check out the previous post to get the simple ES6 based express server over which this was developed.
Here is the repo for the passportjs-local, mongodb simple setups with ES6 classes.