If all surrounding edges on a surface have been rounded/beveled with the blend feature, the Create new sketch on selected surface [Generate sketch on selected face] function can no longer be used on this surface. You can recognize this by the missing display of a coordinate system.[83]
All 4 edges rounded by blend: "Create new sketch on selected surface [Generate sketch on selected face] " not applicable in this situation
If there is at least one "free" edge, the Create new sketch on selected area [Generate sketch on selected face] function can be used.
If one edge is processed by sketch (rounded or chamfered) and the other 3 by blend, the Create new sketch on selected surface [Generate sketch on selected face] function can be used.