Share contents/posts between sites in a WordPress 5.6

Question

I have a client that installed Wordpress 5.6 with multisite enabled .They currently have four websites listing products they sell on the domains:

https://www.example.com
https://www.example.uk
https://www.example.ca
https://www.example.ae

When my client updates a wp_post like Ibanez GRG121DX 6 string guitar, they need to do it four times, one for each of the websites.

How can my client update the product just once and have it syndicated to all four domains?

I see this question has been asked before, but they are all very old questions with old answers. I'm looking for an answer relevant to the year 2021.

Asked in 2017, not answered: How to setup shared content between main site and subdomain?

Asked in 2012, but not sure if it's still relevant? How Can I Centralize Content Usage and Approval in a WordPress Multi-Site installation

Answer 1

In the multisite you can try the switch_to_blog() and restore_current_blog() functions.

Here the documentation: https://developer.wordpress.org/reference/functions/switch_to_blog/.