By far the most common way Shakyamuni is depicted when seated, his right hand does the ‘calling Earth to witness’ gesture and his left hand is in the meditation mudra. If there are no dharma wheels on the soles of his feet and in the palm of his left hand it could be Akshobhya in his buddha appearance.
Tibetan sculptures normally depict the historical buddha with a monastic robe that covers only the left shoulder, the edge of which he often holds in his left hand, as on the Pala-style example above.
Occasionally the robe is made of patchwork. This buddha has a dharma wheel on the sole of his feet and in the palm of his hands, thus indicating that it is the historical buddha.