Use the Text tool, make a text field where you want it, right-click, select Autotext... See figure
You can insert any Project Info (like initials) along with system info, file path etc. If I do this on a Master layout, I get what I want automatically on any of its children.
AC4.1-AC24SWE-25INT; OSX11.5; MP5,1+MBP16,1