There isn't a native feature to create a "New Smart Object Via Copy" for a Linked Smart Object.
There are times where users wish to break the association between linked SO layers to behave the same as embedded SO layers, providing independent control of a layer so that it doesn't update based on the original.
My idea/feature request is to add a new command for "New Linked Smart Object Via Copy".
The existing "New Smart Object Via Copy" command would be renamed to "New Embedded Smart Object Via Copy" so that things were crystal clear.
As an example, I created a couple of scripts to create a "New Linked Smart Object Via Copy" that breaks the association to the original file in a similar way as the native command does for Embedded Smart Objects:
https://community.adobe.com/t5/photoshop-ecosystem-discussions/why-is-new-smart-object-via-copy-grey...
https://community.adobe.com/t5/photoshop-ecosystem-discussions/please-fix-how-relink-to-file-and-rep...