Final answer:
Eumetazoans are characterized by having at least two embryonic germ layers, body symmetry, and internal digestion with a digestive tract, features absent in Parazoans like sponges.
Step-by-step explanation:
The traits that are seen in ALL Eumetazoans, but are absent in Parazoans, include animals having a minimum of two germ layers during embryological development, which means that all Eumetazoans are either diploblastic or triploblastic. Additionally, Eumetazoans exhibit some form of body symmetry which can be radial or bilateral symmetry, and they have internal digestion along with a digestive tract. Significantly, while Parazoans like Porifera (sponges) do not have true specialized tissues derived from embryonic germ layers, Eumetazoans do have these specialized tissues. It is also worth noting that motility is not exclusive to Eumetazoans as some Parazoans do possess the ability to move at certain life stages.