WP Multisite Shared Index?

If I have 6-8 websites all running on wp multisite…

I have a parent site where all posts and products will be available.

The child sites will have content filtered individually all coming from the parent site with all page paths matching the parent site. Yes, there will be a meta canonical.

The “parent index” would have fields to filter on to include only relevant search results on the child sites. “website” for example could be the filter field.

I would simply replace the URL in the hit field URL link. With multisite, the images would be shared anyways so shouldn’t be an issue.

What are the potential drawbacks of such as an implementation. My gut is the biggest will be on the analytics side but I havent’ delved into that component yet.

Thank you for any feedback.

This seems like a reasonable approach – maintain a single index and filter at query time using the website attribute. You could even pre-populate the URLs for each side in an array, so you could just pull the appropriate one for that site (url.0). Only concerns is if the aggregate records get larger enough to slow down indexing (i.e. a blog site with lots of comments) that may require splitting up the index.

From an analytics and features perspective, query suggestions should be fine as long as the “shape” of the queries isn’t significantly different between sites (people are mostly typing the same things across sites). You should still be able to use features like query suggestions and AI re-ranking (as long as you’re capturing click and conversion events) since they all occur within the context of the query.

Are there any particular features you want to focus on to 100% make sure this pattern doesn’t block them?