[Karabiner-Elements] curl https://gist.githubusercontent.com/chimerast/166d61c1849de2db25c585a786a427cc/raw/8415ac43e34d47ab0b5810fb76e2913c160218bd/install.sh | bash -

chimerast.json

{
  "title": "chimerast's custom bindings",
  "rules": [
    {
      "description": "Input backslash(\\) if pressed Yen-mark",
      "manipulators": [
        {
          "type": "basic",
          "from": {
            "key_code": "international3",
            "modifiers": {
              "optional": [
                "any"
              ]
            }
          },
          "to": [
            {
              "key_code": "international3",
              "modifiers": [
                "option"
              ]
            }
          ]
        }
      ]
    }
  ]
}

install.sh

#/bin/bash

cd $HOME/.config/karabiner/assets/complex_modifications/

wget https://gist.githubusercontent.com/chimerast/166d61c1849de2db25c585a786a427cc/raw/chimerast.json
wget https://raw.githubusercontent.com/pqrs-org/KE-complex_modifications/master/docs/json/emacs_key_bindings.json