Hello ccarroll
I think that you should try using the segments from your directory. https://www.qualtrics.com/support/iq-directory/segments-tab/#About
Create a directory segment based on the status (opted out), the segment will be updated automatically, with that you wont have to filter in each list, you would have the opted out contacts in one place and after that create a workflow to get notified about contacts that are being added to your segment https://www.qualtrics.com/support/survey-platform/actions-page/events/experience-id-segments-events/

Thank you for your reply jcgallont
I've already tried this out and unfortunately it doesn't work, the segment is pulling opt out from the directory and not the list. My unsubscribes are getting isolated to lists if that makes sense.
I've deployed a survey to a list and had 3 opt outs. These are showing as opt outs for the list, but not the overall directory.

Yes, I understand. Thats because your respondents are opting out from the List, they have to pick where do they want to opt out from :/

I know - this is now a massive issue for me, as Legal have mandated something that can now only be achieved by a quite tedious manual process.
Appreciate your help, doesn't appear there is going to be a simple solution here.

Circling back on this one to update for anyone else who faces this in the future.
What I've got to as a more effective workaround is a respondent funnel dashboard, which using filters identifies anyone who has opted out of the directory or a list in the last x number of days and returns those members into a record grid table. The dashboard then has been set up to export itself and send to me each week. This at least delivers a list of who I then need to kick off an internal process with, without having to manually click through each contact list.