Just as well as ACF lets you define fields in discrete namespaces to keep it from updating metafields from other apps, you can also use it to handle metafields defined by other apps.
ACF features an easy-to-use wizard to find existing metafields created by other apps and will automatically reuse any existing values once a definition is in place.
From within the field definition dialog for each scope, click the "Add field" button near the top: