With Privy, you can pregenerate self-custodial Ethereum and Solana embedded wallets for existing users, or create a new user with other login methods, like an email address or phone number, without requiring the user to login.
You can even send assets to the wallet before the user logs in to your app for the first time.Once the user associated with the account logs in, they will be able to access the pregenerated wallet and any assets sent to them.