The ornamental design for a knifebladegrip, as shown and described.
FIG. 1 is a front top perspective view of a knife blade grip showing my new design;
FIG. 2 is an enlarged side view thereof;
FIG. 3 is an enlarged front view thereof;
FIG. 4 is a top view thereof;
FIG. 5 is an enlarged back view thereof; and,
FIG. 6 is an enlarged bottom view thereof.
Those portions of the figures that are presented in broken lines merely illustrate the environment of the design and are not part of the claimed design.