This article explains how to create, save, and use custom brushes in Photoshop Elements 2019 for Windows and Mac.
Creating Custom Brushes in Photoshop Elements [Cloud Brushes]
Here's how to create a custom shape brush in Photoshop Elements:
Open Photoshop Elements and select File > New > Blank File.
Set the width and height to 400 pixels, set the background content to white and select OK.