Very Close to a final answer here #285 thanks to @arsaboo

packages/network.yaml

@@ -20,12 +20,15 @@ sensor:
                   'Entry Alarm Panel',
                   'Dash Button',
                   'Master Bedroom Roku',
+                  'Brother Printer',
                   'Wii',
                   'Withings Scale'
-                  ]) -%}
-              {{ item.attributes.friendly_name }}
+                  ])
+                  and(as_timestamp(now()) - as_timestamp(item.last_changed)) > 600 -%}
+              {{ item.attributes.friendly_name }} - {{((as_timestamp(now()) - as_timestamp(item.last_changed))/60) | round() }} minutes
               {%- if not loop.last -%}
-                {{', '}}
+                {{'
+                '}}
               {%- endif -%}
             {%- endfor -%}
           {%- endfor -%}