The ornamental design for a trailerhitch with shackle, as shown and described.
FIG. 1 is a front perspective view of a trailer hitch with shackle, showing my new design;
FIG. 2 is rear perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is a bottom plan view thereof.
The broken lines in the figures are for the purposes of illustrating portions of the trailer hitch with shackle, which form no part of the claimed design.