ArcGIS Pro, Spatial ETL, Workbench - Creating a feature class input

Hi @waltersgareth, I think you want to allow the user to select a feature class for each run through a parameter. If so, you can define such a published user parameter with these steps.

1. Change the reader feature type to a single merged feature type.

Check the Merged Feature Type checkbox in the feature type properties dialog. After that, the reader feature type can read features from any feature class specified via the Feature Types to Read parameter of the FGDB reader.

2. Create a published user parameter to select a feature class which should be read.You can create a user parameter linked to the Feature Types to Read parameter, through the Navigator window.1) Right-click on the Feature Types to Read parameter and select the Create User Parameter in the context menu. Note: I created this screenshot with FILEGDB reader so there are differences from your GEODATABASE_FILE parameters, but I think the Feature Types to Read is common to both.

2) Configure the parameter with the Modify Feature Types List dialog which will be opened when you select the menu item above.

 

I cannot test how the new parameter would reflect to the interface of ArcGIS Pro, since I don't have Esri Data Interoperability extension. Hope it works as expected.