Linking multiple ACF installations
When you have multiple related ACF installations, like multiple language shops, shops for different regions or shops for different environments (test, staging, live), you can link your ACF installations together for easy management of custom fields.
Choose the store, you'd like to use as the "master store" and from that shop's ACF dashboard, click the "Open settings" button to open the settings dialog:
In the "Linked stores" area, type one of your related stores' ".myshopify.com" domains (just type the part before .myshopify.com) and press Enter.
For each linked store, you are required to input that store's API key to verify your access. You find your other store's API Key at the top of the very same dialog, but of course from its own Settings dialog. When you enter the correct API key for the linked store, you'll see the domain shown in blue like in the example above. Add more stores in the same manner.
Then select your synchronization option.
While the "Complete" synchronization option is recommended, only select this, if you'd like the field definitions to be mirrored 100% across your linked stores. The "Partial" option is safer, but may lead to duplicated section definitions, if these were set up manually prior to a sync (only applies to sections created before September 20, 2020)
Click Save and your linked stores will be ready for easy synchronisation of custom field definitions.
You can mix and match the linking as you please, so for example store A links store B and vice versa or store A links store B + C and store B links store D. Plan this carefully to avoid confusion