The geometry node performs Inset and Outset with a constant offset. It works with both, individual and multiple faces. 

Why This Product

The Inset feature is currently missing in Blender Geometry. It can be developed easily in geometry nodes, but with major limitations.  To get a better understanding of these limitations, please watch this YouTube video. Inset with Geometry Nodes in Blender 3.2 (by Blender Bash)

Inset/Outset with Individual Faces.

Inset/Outset with Multiple Faces.

Inset/Outset with Mixed Faces.

Comparison Default feature with this product.

Bonus Tools

The tools, I developed during the development of the Road Generator product. They are even helping me with new developments, which will be published very soon.  

Show Normals (Debugging Tool).

Axis (Dev Tool).

For more details, see this product. Axis (Dev Tool)

Proportional Deforming Tool.

For more details, see this product. Proportional Deforming