The manual says (on page 70 - Editing Clefs, Keys, and Time Signatures):
If you hold down Alt/Opt when double-clicking, all symbols at the same position are changed accordingly.
(Cubase_Pro_Score_12_Score_Layout_and_Printing_en.pdf - WebHelp version)
This doesn’t work on my computer (OpenCore macOS Ventura 13.3.1). How about yours?