The Blockstream Green desktop app allows you to manage multiple wallets on the same device.
Note: Wallets should not be confused with accounts. Both on desktop and mobile, you can create multiple accounts per wallet.
Desktop
When starting up the Blockstream Green desktop app for the first time, you will be prompted to create a new wallet or restore an existing wallet.
To add additional wallets for the same or other networks (Bitcoin, Liquid, and testnet), the process is exactly the same. After adding your first wallet, just go through either process again:
After adding multiple wallets to the Blockstream Green desktop app, you can switch between them via the left sidebar (click the home icon).
Note: The PIN to your wallet is tied to the device you use to access the wallet, while the two-factor authentication (2FA) method is tied to the wallet itself. That means if you restore an existing wallet on a new device, you will need to set a separate PIN. However, you will use the same 2FA method across all devices that access your wallet.