Things have changed dramatically since 4.3, and brushes are this biggest. If you would like to find those brushes, Daniel Lari posts a video of where you can get them: https://www.pepe-school-land.com/grease-pencil-brush-pack
Here is his short how-to video on how to install: https://www.instagram.com/p/DH8SN4rNyL1/?hl=en
I’ll try and post some updated stuff next week, but personally, I don’t like how Brushes are currently either assets you cannot edit (like this file) or they have to be manually dropped in a folder and pointed to through Preferences>>File Paths>>Asset Libraries. I’ve created a small pack for you here: https://cgcookie.com/downloads/paul-s-grease-pencil-3-0-brush-pack
And if you follow this video: https://www.youtube.com/watch?v=FHu6X_N3qjU you should be able to manage and create your own custom brushes in the new system
