There are less default brushes after changing devices
From Clip Studio Paint Ver. 1.10.10, the default brush lineup has been changed.
You can download the previous default brushes from Clip Studio Assets.
Pens & Brushes_Ver.1.10.9
Decorations(1)_Ver.1.10.9
Decorations(2)_Ver.1.10.9
Follow the instructions on the following page for how to import the downloaded brushes.