Answer: MANTA RAY VISION
The treasure map was printed on aged parchment. The shovels were stencilled with invisible ink, and while not required to solve the puzzle, represented an additional hint if viewed under UV light.
The 6 X's on the map (and the shovels) are on a grid. The transformed phrases can be put in the grid so that the X's in the phrases are written over the X's on the map. This is unique with assuming that the trees drawn on the map are obstacles.
Finally, read every letter that intersects the dotted path in order (these are also the locations of the shovels).
The final answer is MANTA RAY VISION - a phrase that also has the earlier transform property.