Reproduction steps:
1. Create a new HDRP Template project
2. Create an HDRP Lit Shader Graph (.shadergraph)
3. Create a new Standard Surface Shader (.shader)
4. Copy Lit Master Generated code into previously created Standard Surface Shader
5. Create a Material from the Standard Surface Shader
6. Try toggling "Motion Vector For Vertex Animation" option on the Material

Expected result: the option toggles like it would in a Material created from original Lit Shader Graph
Actual result: you are unable to toggle the "Motion Vector For Vertex Animation" option

Reproducible with: HDRP 6.9.2 (2019.2.18f1), HDRP 7.1.7 (2019.3.0f5, 2020.1.0a19)
Not reproducible with: HDRP 4.10.0 (2018.4.15f1), HDRP 6.9.0 (2019.2.18f1)

Notes:
1. This reproduces with HDRP StackLit, Fabric, Eye Shader Graphs
2. I was not able to find any other option that would behave this way. For all other options/Shaders if the option is visible, then it is possible to toggle it just like in the original Shader
3. This is a Package regression. The issue does not reproduce with HDRP 6.9.0 but reproduces with higher versions of HDRP (tested 2019.2.0b10, 2019.2.18f1)