@Alexbbrown I would rather not -- the default behavior is I think good. If I write

"hi @-local-user, I think @-remote-user sucks" and the "local" option is checked, it posts local. and it renders "local-user" as a hyperlink, and "remote-user" as plain text, so there is a clear visual indication that the second user cannot see the message -- and if you want to change that, you can delete and redraft your post