KDE5 shortcut for moving window to another workspace

In Kubuntu 17.04 Zesty, in System Settings > Shortcuts > Global Shortcuts > System Settings, you have an option Window One Desktop [Down/to the Left/to the Right/Up]. Which is a slightly different place from what the other answer says.

In the System Settings > Shortcuts > Global Keyboard Shortcuts > KWin, you have an option Window One Desktop [Down/to the Left/to the Right/Up], as well as some other options for moving windows to other desktops or screens.

(I found my solution by searching for kwin move window desktop and selecting time period last year and found this link)

Edit: afterwards I also had a problem that the KWin option was not available from the dropdown. Restarting KWin fixed it: kwin --replace.