Hi,
Regarding the size for YouTube and Gmail, and the creation date of the userlist, you are correct. Those are currently not available in the AdWords API. As for the "Usage Status", only the
AccountUserListStatus is available. That said, you would not be able to determine via the AdWords API as to which other accounts the userlist is shared with.
If you wish to learn where you can view the usage status via the Google Ads UI, you can reach out to the product experts via the
Google Ads Community Forum as they are better equipped to assist you regarding this concern.
Thanks and regards,
Peter
Google Ads API Team

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