Snippets reside within a project so the nearest you would get
is maintaining them in one project, importing them and reimporting
whenever you make a change.
To create links to topics in other projects without importing
I think the only way to do it would be to manually enter the
relative path as it will be between the two outputs. Will you
always know that?
I don't understand why you don't want to go to merged help as
it looks like your scenario is just crying out for it?
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