When disabling the "i18n" use flag for Gnome, "gnome-base/libgnomekbd" should be keeped as a dependency (as it's needed to show the keyboard layout in settings).
what concrete error are you getting?
The keyboard layout display button doesn't work in region&language panel (does not do anything), as it calls a helper binary that libgnomekbd ships to display the visual keyboard with the keys shown as they are in that layout (and pressing keys will visualize what was pressed). This was a change done for bug 509130 originally, I believe, though now libgnomekbd got an updated release again (but still requires X, which is fine for wayland as the visual keyboard tool is a separate process and just goes to Xwayland).
Lets see how much new hate we get from pulling this in unconditionally. I don't like some button being there, and it not doing anything with no explanation. libgnomekbd received a 3.22.0 release as well, someone did some necromastery (making it optional was partially justified before by it being dead, I believe). commit 06947f025a4b40e8b9752df158bad875e72ea97a Author: Mart Raudsepp <leio@gentoo.org> Date: Sun Mar 19 14:21:33 2017 +0200 gnome-base/gnome-control-center: fix build with USE=-wayland, always pull in keyboard layout display tool Gentoo-bug: 539290 Gentoo-bug: 613192
