This is a tricky one Xue,
The medial cuneiform like other tarsal bones can have a fairly rough surface texture as there is no hyaline cartilage covering it and no major tendon attachment in this area.
I think of these parts of the skeleton as having a “rustic” appearance.
So I am not too worried about the bony irregularity.
There is no colour Doppler signal in the soft tissues and the other side is fairly similar.
With this clinical history if there is point tenderness I would be thinking of a stress reaction in the bone from the track training.
It is not evident on the ultrasound although you could argue that the soft tissues are slightly more echogenic on the symptomatic side it is fairly subtle.
If there is persisting pain I would treat it as a stress reaction and see if it improves, another option is to use MRI or nuclear medicine to evaluate further.
Steve