In my opinion, you should use wp-query. Using a sidebar for this purpose will yield problems in the long term.
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SEO: Sidebars are taken as “aside” content, which is considered less relevant content by search engines.
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Editor: The editors for the sidebars are much worse than post editors.
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Reliability: Any change to containers added in function will reset all content and setup.
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Scalability: More functions available to work with on post.