Hi @Joel Wilcox ,
SharePoint does not have a native feature to apply a content reuse solution as allowed by other platforms such as XML-based solutions like DITA, MadCap Flare, etc.
If the web parts such as library and list that need to reference data sources, changes to the data source will be synchronized to the web part. If it is other types or custom web parts, there is currently no available method. It is recommended that you go to the Partner Center to see if there is a better solution.Have a nice day!
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