Suggested by Grethe Byrkjedal – Under Review
Missing possibility to filter on records with no value on related fields in lists.
Status Details
Thank you for your feedback. Currently this is not in our roadmap; however, we are tracking it and if we get more feedback and votes, we may consider it in the future.
Sincerely,
Johan Hoffmann
PM, Microsoft

Hi Grete!
Have you tried to add is exactly: "" as a filter parameter for retrieving blank fields?
It's my go-to, and it works for most fields.
//Sarah