The barlines at the end of the system are hidden. They will not print and if you uncheck View>Invisibles>Hidden objects, you will not see them in the display.
I don't know how to remove the barline at the start of the systems, if that is what you want to do. You can't overlay an invisible barline on it, and you can't delete it. The Engraving Rules setting in Barlines only applies to single staves.
I assume someone else will know what to do.
--
Bob
I don't think it's what you want, but if you do wish to remove the systemic initial barline on each system, select the first bar of the system, open the Inspector and untick the box for 'Initial barline' in the Bars section. This also removes the brace, and that's impossible to avoid.
Hope that helps
Jody
--
music editor and engraver
Sibelius Ultimate on a Mac Studio running OS 14.6.1