Send erc20 token transfer transaction to gnosis safe

distribute.ts

import { run, ethers } from "hardhat"
import Safe, { SafeTransactionOptionalProps } from "@gnosis.pm/safe-core-sdk"
import { EthersAdapter } from "@gnosis.pm/safe-core-sdk"
import { MetaTransactionData } from '@gnosis.pm/safe-core-sdk-types'

const safeAddress = "0xfA64EE..." // on rinkeby testnet
const tokenAddress = "0x18B225..." // on rinkeby testnet

const TokenFactory = await ethers.getContractFactory("TokenContract")
const token = TokenFactory.attach(tokenAddress)

const [owner] = await ethers.getSigners()

const ethAdapter = new EthersAdapter({
  ethers,
  signer: owner
})

const safeSdk = await Safe.create({ ethAdapter, safeAddress })
const safe = await safeSdk.connect({ ethAdapter, safeAddress })

const unsignedTransaction = await token.populateTransaction.transfer("0x5d07C6...", 100)

console.log(unsignedTransaction)

const transactions: MetaTransactionData[] = [{
  to: tokenAddress,
  value: "0",
  data: unsignedTransaction.data!
}]

const safeTransaction = await safe.createTransaction(transactions)

console.log(safeTransaction) // returns with a different "to" than specified in line 27

const owner1Signature = await safe.signTransaction(safeTransaction)

console.log(`owner signature: ${owner1Signature}`) // returns undefined

Thx a lot for your help @germartinez , greatly appreciated 🤗 ... I'll read up on all this and get back if I have further questions.

You are all very supportive ❤️ – Thx again!

Quick update: I got it to work 🎉 thx @germartinez @rmeissner and @DmitryBespalov!

I'll try to write something up to have others also benefitting from my learnings.