Hi, I have a post about this bug in the general forums, but I have confirmed with DC, AD, and EP emperors that after the series of maintenances last week, it introduced a bug where emperors lose their emp passive abilities after logging out or zoning, even zoning into a delve in cyrodiil. This is in the ravenwatch campaign, I cant speak for any other campaigns.
Below is a link to the main post where you may find some more details.

https://forums.elderscrollsonline.com/en/discussion/600840/emperor-powers-are-lost-after-switching-characters-and-changing-back-pc-na#latest