How to reference template partials in a plugin vs theme?

I have template parts working well per this sample (https://displayposts.com/2019/01/04/use-template-parts-to-match-your-themes-styling/), but I’d like to reference the partials directory in my custom plugin instead of in my theme.

I tried changing get_template_part to include and require_once, but none of these methods worked.

Any ideas of how I can do this?

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