Karabiner Elements JSON configuration for an external keyboard (And RDP specific things)

keyboards.json

{
  "title": "DWE",
  "rules": [
    {
      "description": "Keyboards",
      "manipulators": [

        {
          "description": "Space is switch to external keyboard input source", "type": "basic", 
          "from": {"key_code": "spacebar"}, "to": [{"select_input_source": {"input_source_id": "com.apple.keylayout.German-DIN-2137"}}, {"key_code": "spacebar"}],
          "conditions": [
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]},
            {"type": "input_source_unless", "input_sources": [{"input_source_id": "com.apple.keylayout.German-DIN-2137"}]}
          ]
        },
        {
          "description": "Space is switch to internal keyboard input source", "type": "basic", 
          "from": {"key_code": "spacebar"}, "to": [{"select_input_source": {"input_source_id": "com.apple.keylayout.SwissGerman"}}, {"key_code": "spacebar"}],
          "conditions": [
            {"type": "device_unless", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "Internal Keyboard"}]},
            {"type": "input_source_unless", "input_sources": [{"input_source_id": "com.apple.keylayout.SwissGerman"}]}
          ]
        },

        {
          "description": "Home is jump left (Not for RDP)", "type": "basic",
          "from": {"key_code": "home"}, "to": [{"key_code": "left_arrow", "modifiers": ["command"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },
        {
          "description": "End is jump left (Not for RDP)", "type": "basic",
          "from": {"key_code": "end"}, "to": [{"key_code": "right_arrow", "modifiers": ["command"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },

        {
          "description": "CTRL is command (Not for RDP)", "type": "basic", 
          "from": {"key_code": "left_control"}, "to": [{"key_code": "left_command"}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },

        {
          "description": "ALT+c is control+c (Not for RDP)", "type": "basic", 
          "from": {"key_code": "c", "modifiers": {"mandatory": ["left_option"]}}, "to": [{"key_code": "c", "modifiers": ["left_control"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },

        {
          "description": "ALT+r is control+c (Not for RDP)", "type": "basic", 
          "from": {"key_code": "r", "modifiers": {"mandatory": ["left_option"]}}, "to": [{"key_code": "r", "modifiers": ["left_control"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },

        {
          "description": "CTRL+Left Arrow is command (Not for RDP)", "type": "basic", 
          "from": {"key_code": "left_arrow", "modifiers": {"mandatory": ["left_command"], "optional": ["shift"]}}, "to": [{"key_code": "left_arrow", "modifiers": ["left_option"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },
        {
          "description": "CTRL+Right Arrow is command (Not for RDP)", "type": "basic", 
          "from": {"key_code": "right_arrow", "modifiers": {"mandatory": ["left_command"], "optional": ["shift"]}}, "to": [{"key_code": "right_arrow", "modifiers": ["left_option"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },

        {
          "description": "CTRL+Tab is CTRL+Tab (Not for RDP)", "type": "basic", 
          "from": {"key_code": "tab", "modifiers": {"mandatory": ["left_command"], "optional": ["shift"]}}, "to": [{"key_code": "tab", "modifiers": ["left_control"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        },

        {
          "description": "Alt+Tab is option+Tab (Not for RDP)", "type": "basic", 
          "from": {"key_code": "tab", "modifiers": {"mandatory": ["left_option"]}}, "to": [{"key_code": "tab", "modifiers": ["command"]}],
          "conditions": [
            {"type": "frontmost_application_unless", "bundle_identifiers": ["com\\.microsoft\\.rdc\\.osx\\.beta", "com\\.microsoft\\.rdc\\.macos", "com\\.microsoft\\.teams"]},
            {"type": "device_if", "identifiers": [{"vendor_id": 9610, "product_id": 1, "description": "USB Keyboard"}]}
          ]
        }

      ]
    }
  ]
}