You can create a chamfered corner at the location of a vertex using
Mesh > Chamfer Vertices or
Bevel in the
Modeling Toolkit.
Chamfer removes a vertex and creates a chamfered corner.
To chamfer a vertex
Select the vertex you want to chamfer.
Select
Edit Mesh > Chamfer Vertices in the main menu or click
in the
Modeling Toolkit.
In the
In-View Editor that appears, adjust the
polyChamfer attributes.