Best way to feed my sites

Greetings,
I have several WP‘s that have much the same content, providing info to locally flavored versions of a theme. I manage each WP as it’s own entity, and it’s a cumbersome process.

What’s the best way to set up one WP that serves up articles to the other sites? RSS feed or a multi-site? I’d like to be able to manage which articles go where, some go to all, some to just one. Hope I’m making sense.

https://GreenOrlando.com
https://GreenBrevard.com
https://GreenFtLauderdale.com

Thanks for any guidance.
??

-e

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