tx-signer.js

const ethers = require('ethers');

async function main() {

  let privatekey = '<<PRIVATE_KEY>>'; // Yeah this should be done through an env var, I know but this is a f gist
  let wallet = new ethers.Wallet(privatekey);

  console.log('Using wallet address ' + wallet.address);

  let transaction = {
    to: '0xc1fd1272fA7B402FfE445e890F888247d66d8F9F',
    value: ethers.utils.parseEther('0.001'),
    gasLimit: '21000',
    maxPriorityFeePerGas: ethers.utils.parseUnits('5', 'gwei'),
    maxFeePerGas: ethers.utils.parseUnits('90', 'gwei'),
    nonce: 227,
    type: 2,
    chainId: 1
  };

  // sign and serialize the transaction
  let rawTransaction = await wallet.signTransaction(transaction).then(ethers.utils.serializeTransaction(transaction));

  // print the raw transaction hash
  console.log('Raw txhash string ' + rawTransaction);

}

main();