When running anaconda from the Workstation live image (i.e. under Wayland), switching keyboard layouts using the key combo (usually alt+shift) does not work. Switching layout by clicking the layout indicator does work.
I'm guessing that what anaconda does to configure the switch key combo simply doesn't work under Wayland.
Proposing as a Final freeze exception. Not proposing as a blocker as the more serious https://bugzilla.redhat.com/show_bug.cgi?id=1331382 was rejected as a blocker for F24, so there's no reason to think this would be accepted as a blocker. But layout switching is important to users of multiple layout languages, so a fix for this would be nice if possible. If not, we can document to click the switcher instead of using the key combo.
Discussed during the 2016-10-31 blocker review meeting: 
The decision to classify this bug as an AcceptedFreezeException was made as this is an installer issue and therefore cannot be fixed with an update.
I've assigned a custom key combination in GNOME wayland and it works fine.
Using Gnome.org in lieu of Wayland, the keyboard switching works for me, but, it does not result in a change to the Gnome keyboard layout INDICATOR (top panel right side).
My choice for layout change was simultaneous control key operation.
Same OR SIMILAR results as Dwaxeiption.
This bug appears to have been reported against 'rawhide' during the Fedora 26 development cycle.
Changing version to '26'.
"I've assigned a custom key combination in GNOME wayland and it works fine."
This is about using the switcher combo that anaconda configures. If you select some locales, anaconda will automatically select two keyboard layouts, and try to configure a specific key combination (usually alt+shift) to switch between them. There is also an option in the anaconda KEYBOARD screen to configure one of several different switcher key combinations.
None of this actually works under Wayland; any combo anaconda thinks it's configured as a layout switcher combo does not in fact switch the layouts. But anaconda's UI still tells you it's configured a switcher combo and that you can use it to switch layouts.
Still the same issue with F28 Beta.
I switched the keyboardlayout using the gnome-settings dialog.
anaconda stil showed the us layout.
after clicking on it it changed to null
a second click crashed anaconda.
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*** Bug 1628859 has been marked as a duplicate of this bug. ***
per the dupe, this is still valid as of F29.
Just wanted to share. I have got to test Fedora Silverblue 29 RC1.5 image and found almost all "alt+<key>" combinations working for me. They can switch the keyboard. But some are not working like "Caps Lock" "Right Alt" "Shift+Caps Lock". I have not checked all the combinations.
This bug is basically about Workstation live images. Installer images like the Silverblue installer image are not affected *during the install* because the installer environment uses X, not Wayland. Post-install, though, Workstation will not respect any switcher combo configured by anaconda for X.
Adam, Thanks for that information.