Similar issue as most have posted here.
First started Friday 12 Jan 2024.
Everything set to Eng(Canadian), all suggested steps tried with no relief from the symptom.
The Spotlight picture is still in a Scandinavian language, and the picture hasn't changed in 24 hours, several reboots or logout/login attempts, so cannot see if the next picture is affected.
Changing from Spotlight, the pictures and Slideshow are in the correct language.