We have a requirement to default the Ship-to Location and Bill-to Location values using Sanbox

We have a requirement to default the Ship-to Location and Bill-to Location values in the Manage Supplier → Manage Site Assignments screen.
We attempted to configure this via Sandbox and Page Composer, but the LOV components for these fields do not expose any value property that would allow setting a default.

We kindly request confirmation on:
The feasibility of defaulting these LOV fields.
Any available workarounds or recommended approaches.

Impact: Users must manually enter Ship-to and Bill-to values for each site assignment, which increases the risk of data entry errors and impacts operational efficiency.