Is there a hack for "Save As..." command?
With the File menu open, press and hold the Option key to get the Save As... command.


Update: Some new users of macOS may be concerned about the discoverability of the command, as it is not visible by default in the Pages menu bar. And most users aren't aware that the Option modifier key can alter the behavior of commands.
An alternate discovery approach that new users can take to discover a command is to go to the Help menu and search for the desired command. A match, if available, would be highlighted, along with its keyboard shortcut, even if it is not directly available in the app menu. The same is illustrated below for Save As... command in Pages for macOS.

The trick works in any native macOS app.