Package.xml to get all the metadata using Visual Studio Code for Salesforce
package.xmlを右クリックして、
ファイルダウンロードしてください。
The Manifest (package.xml) File
your-app
├── README.md
├── sfdx-project.json
├── .sfdx
├── .vscode
│ ├── extensions.json
│ └── settings.json
├── force-app
│ └── main
│ └── default
│ ├── aura
│ ├── classes
│ └── objects
└── manifest
└── package.xml
refer
http://www.infallibletechie.com/2018/12/packagexml-to-get-all-metadata-using.html