How can I assign redundant shortcuts for switching workspaces in GNOME 3?

Yes, this is a dconf setting and the value is an array of strings which means it accepts multiple shortcuts. You can do that via dconf-editor if you navigate to

/org/gnome/desktop/wm/keybindings/switch-to-workspace-1

and turn Use default value OFF then insert Custom value: ['<Super>Home', '<Super>1']

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Or if you prefer CLI you can use dconf or gsettings e.g.

gsettings set org.gnome.desktop.wm.keybindings switch-to-workspace-1 "['<Super>Home', '<Super>1']"

Keep in mind the values must be quoted and separated by comma+space.