only option that comes to mind would be a macro.
I'd suggest you not bother with Layers. You can have a separate sheet format for each set of notes, then use whichever sheet format is appropriate for each project. It's possible to not have a sheet format embedded in a drawing template so that the user will be asked to select a sheet format when starting a new Drawing (see the excerpt below from What's the difference between a sheet format and drawing template?). If you don't want multiple drawing templates then I believe this would be your best option.