distributeXlm_batch.js

const distributeXlm = async (masterAccount, amount, ...walletAccounts) => {
  console.log('distribute xlm')
  let account = await server.loadAccount(masterAccount.publicKey())
  let txBuilder = new TransactionBuilder(account, { fee: 100 })
    .setTimeout(TimeoutInfinite)

  walletAccounts.forEach(w => {
    txBuilder.addOperation(
      Operation.payment({
        amount: `${amount}`,
        asset: Asset.native(),
        destination: w.publicKey(),
      })
    )
  })

  const transaction = txBuilder.build()
  transaction.sign(masterAccount)

  return server.submitTransaction(transaction)
}