The keyboard layout switch is Super + Space. This is how GNOME does it and budgie inherits that method.
On Ask Ubuntu I answered as similar question - you can try this as well - https://askubuntu.com/questions/909316/ubuntu-budgie-how-to-use- altshift-to-switch-keyboard-layouts -- You received this bug notification because you are a member of ubuntu budgie bug busters, which is subscribed to Ubuntu Budgie. https://bugs.launchpad.net/bugs/1687900 Title: Changing keyboard layout problem Status in Ubuntu Budgie: New Bug description: Hello Thank you for Ubuntu Budgie! Budgie is very nice . I use Ubuntu Budgie 17.04 (budgie-desktop 10.2.9). I can't switch between my keyboard layouts (English and Persian) by keyboard shortcut(left Alt + left Shift) or (right Alt + right Shift) but I can switch between them by clicking on Keyboard layout indicator in panel. I have not this problem with Ubuntu Mate 17.04 or Ubuntu 16.04(with Unity) or OpenSuse(with KDE Plasma) before. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntubudgie/+bug/1687900/+subscriptions -- Mailing list: https://launchpad.net/~budgie-remix-bug-busters Post to : budgie-remix-bug-busters@lists.launchpad.net Unsubscribe : https://launchpad.net/~budgie-remix-bug-busters More help : https://help.launchpad.net/ListHelp