The ornamental design for a headwearvisor, as shown and described.
FIG. 1 is a top plan view of a headwear visor showing my new design;
FIG. 2 is a left side perspective view thereof;
FIG. 3 is a front perspective view thereof;
FIG. 4 is a bottom plan view thereof; and,
FIG. 5 is a rear perspective view thereof.
The right side perspective view is a mirror image of the left side perspective view. The broken lines represent environmental structure that form no part of the claimed design.