Available with Data Interoperability license.
Spatial ETL tools are user-created geoprocessing tools that can transform data between different data models and different file formats. You create them with FME Workbench in a translation workspace and save them in a toolbox.
Initiating creation of a new spatial ETL tool opens the Create Translation Workspace Wizard. The wizard prompts you for information about the data source and data destination, then starts FME Workbench with a diagram of your dataflow. You can customize the default dataflow by adding or deleting connectors, inserting transformers, and editing parameters.
Usage
Spatial ETL tools are capable of a wide range of processes and dataflows from simple format translations to complex transformations that restructure geometry and attributes. They can be used as stand-alone geoprocessing tools, published in toolboxes as geoprocessing services 
using ArcGIS Server, or exported as custom formats and utilized in the FME reader gallery.
Possible uses include the following examples:
- Filtering attributes and merging them with other feature classes
- Using attribute values to create unique feature classes on the fly
- Separating data using test criteria
- Creating line features from coordinate values