It's possible to do it manually with files, you settings are saved to settings.txt
and your bindings are saved to bindings.txt
in C:\Users\Username\AppData\Roaming\Diabotical
you can get there by pasting %appdata%/Diabotical
in the Windows explorer address bar or by typing the command /homedir
in the console in-game, then you can move those files to another folder or rename them to something other than "settings" and "bindings" such as "settingsbrother", "settingsme", then make a copy of one of those depending on who is playing and rename it to "settings" so that it's read by the game when you launch it afterwards.