I found these instructions for the older version of font awesome but it doesnt work with fa v5
https://charlouze.github.io/ionic/2017/05/31/Ionic-3-and-Font-Awesome.html
This is the key page:
https://fontawesome.com/how-to-use/use-with-node-js
Install with npm, and then use a deep import to get tree shaking.
Be warned that the tree shaking is a bit wobbly at the moment, and expect things to change somewhat substantially in 5.1. If you have a Pro subscription, follow issue 978. If not, or you just want the tl;dr, follow the instructions in @AaronSterling’s link and once you use library.add() to add any icon declaration, that whole pack will come in.
It works if you end up whole tutorial and add @component FaIconComponent to yours app.module.ts declarations and entrycomponents