How to reproduce:
1. Download the tester-attached fbx model
2. Create a new Unity project
3. Import the URP package(but don't set it as the project's rendering pipeline)
4. Import the downloaded model and inspect its materials
5. Select the model, navigate to the Materials tab and set 'Material Creation Mode' to 'Import via MaterialDescription'

Expected result: the materials are using a Standard shader
Actual result: the materials are using a Universal Render Pipeline/Lit shader

Reproducible with: 2019.4.10f1(URP 7.3.1, 7.4.1), 2020.1.0a19(URP 7.1.5, 7.4.3), 2020.1.5f1(URP 8.2.0, 9.0.0-preview.55), 2020.2.0b2(URP 8.1.0, 10.0.0-preview.26)
Not reproducible with: 2020.1.0a19(URP 7.1.2)
Could not test with: 2018.4.27f1(Material Creation Mode dropdown unavailable)

Notes:
Tested with URP
Before 2020.2.0a12 the default Material Creation Mode used to be 'Standard', meaning it had to be set manually for the issue to occur