Control those who will be notified

Current set up is we have 3 workspaces w/ 1 board each ( this wasn’t private) . Now we had 2 of those boards set to private.

If we can control those who will be notified for our private boards (as the Board owner). Because I noticed that the Board notifications > only customizable for ourselves. or if anyone knows the workaround please share your tips and workarounds.