TransferTransaction API call. For each atomic swap within a single transaction, you’ll need to designate an account to be debited (-) any number of tokens and the corresponding account which will receive those tokens.
Signing Requirements
The private keys for the accounts which are being debited tokens are required to sign the transaction.
Hedera accounts must be associated with the specified token before you can transfer a token to their account. Please see how to associate a token to an account here.