The ornamental design for a washerpunchinsertplug, as shown and described.
FIG. 1 is a perspective view of the washer punch insert plug of the present invention, looking angularly towards a front edge thereof;
FIG. 2 is a side elevational view of the washer punch insert plug of the present invention, which side view is of the first side of said design;
FIG. 3 is a side elevational view of the washer punch insert plug of the present invention, which side view is of the second side of said design;
FIG. 4 is a side elevational view of the washer punch insert plug of the present invention, which side view is of the third and last side of said design;
FIG. 5 is a top or plan view of the washer punch insert plug of the present invention; and,
FIG. 6 is a view of the bottom or back end of the washer punch insert plug of the present invention.