The ornamental design for an attachment for a poweredsharpener, as shown and described.
FIG. 1 is a right side view of the design.
FIG. 2 is a left side view of the design of FIG. 1.
FIG. 3 is a front end view of the design of FIG. 1.
FIG. 4 is a rear end view of the design of FIG. 1.
FIG. 5 is a top view of the design of FIG. 1.
FIG. 6 is a bottom view of the design of FIG. 1; and,
FIG. 7 is an isometric view of the design of FIG. 1.
The broken lines in these drawings serve to illustrate the environment in which the claimed design is associated. The broken lines form no part of the claimed design.