How Crossposting Plugins Work with Images

Before we continue, let me clarify how both of my crossposting plugins actually process the images (or any other files).

Type of attachmentHow it is processed by the plugin
Featured ImagesWill be copied to sub-sites with their data (just once). If an image with the same filename exists, it will be used instead.

Read this if you need to use original images (for the multisite version of the plugin only).
Images in post contentAs long as the post content only holds image URLs, the plugin does nothing with them. So, there is no need to duplicate every post image from the article (there could be hundreds of them) as long as we can use their original URLs. We also win in performance.

But the not-multisite version of the plugin has an option in settings to copy the content images to subsites.
Images or any files in custom fields (added with ACF or any other plugin)Usually attachments are stored in custom fields as their IDs. Please check this guide to find out how to make them to be copied to subsites.
Images or files in ACF blocksThey are supported with this add-on. Images are going to be copied to subsites.

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