Yes it is possible in NX through various means. In your example you can edit the Element Associated Data and define a new thickness for the element or unique thickness values at each corner node of the element. For properties supported by Element Associated Data, this is a good way to go.
Not all properties are supported by Element Associated Data. One example is an element's material. The material is defined in the mesh collector of the element's mesh. To accomodate edits at the mesh level, NX supports an element extract command that removes selected elements from their mesh and places them in a new mesh. That new mesh can then be edited in terms of the collector it resides in and its mesh associated data.
Both of these commands are found in the Edit Element menu.
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Product Engineering Software
Siemens Industry Sector
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