When you do an asset import task, of an interchange supported format, UE will use the default asset interchange pipeline stack.
So you are using interchange. If you want to customize it you could:
- copy the default asset interchange pipeline,
- change the settings,
- create a new pipeline stack for asset import,
- add the copied/modified pipeline in it,
- and change your default import pipeline stack to use that one.
You can skip 3, 4 and 5 if your replace the existing pipeline in the default asset pipeline stack.
Now your asset import task will import using your interchange pipeline with your custom settings