Yes, you could do this, but it would be very complex and not something that ACF would let you do out “of the box”. You would need to build your options page and then every time the page is saved you’d need to apply the changes to each page that it needs to apply to. I can think of other possibilities but they just get more and more complex.
Also, this would in the end be confusing for most of the clients I deal with, since they need to figure out where to edit it and what applies where. It is far easier for clients to understand that when they want to alter something on a specific page that they edit that page.
