Explain how to create a partial fillet using "Cut Extrude".
Procedures:
[1] Drag and drop "Cut Extrude" on the Shape catalog at the center of the part edge.
[2] Adjust the extrusion direction with TriBall to parallel to the edge.
(Tune the arrows of the red circle and the edges of the red arrows below to be parallel)
[3] Right-click "H Block" feature and select "Edit Cross-section" from the menu.

[4] Create a fillet with "Center Radius" on the Sketch tab.
[5] Delete unnecessary lines with "Trim".

[6] If you want to change the radius of the fillet, select the block hole and adjust it with the handle of the size box.

Please refer to the video below.