There is a partial answer here:
The command to use is 'gsettings` and the actual settings to use you can find by using:
dconf watch /
in the terminal, while you adjust the settings. You get a bunch of statements like this:
/org/gnome/desktop/wm/preferences/theme
'elementary'
/org/pantheon/desktop/gala/behavior/hotcorner-bottomleft
'custom-command'
/org/pantheon/desktop/gala/behavior/hotcorner-bottomright
'none'
/org/pantheon/desktop/gala/behavior/hotcorner-custom-command
'xset dpms force off'
You want to reformat these lines into commands like this:
gsettings set org.gnome.desktop.wm.preferences theme 'elementary'
gsettings set org.pantheon.desktop.gala.behavior hotcorner-custom-command 'xset dpms force off'
gsettings set org.pantheon.desktop.gala.behavior hotcorner-bottomleft 'custom-command'