Add reusable component does not use the item type they were imported with machinery library installation tool.
Solution
he machinery library is based on part family templates. If you add such a Reuse File into your assembly, the member is created.
If the part family spreadsheet contains the attribute "DB_PART_TYPE" the created member has the Item Type defined in the part family spreadsheet table.
To change this behavior you need to modify the part family table of your reuse parts. You can either remove "DB_PART_TYPE" at all from the part family table, or change the values in the spreadsheet for your needs.
There is no functionality to change this for all reuse parts automatically.
Notes and References
Hardware/Software Configuration
Platform: INTL64
OS: window
OS Version: 764SP1
Product: NX
Application: KDA
Version: V9.0.3
Function: REUSE_LIBRARY
Ref: 001-7947511