Years ago I had my wifes 5(s?) screen replaced. They asked for the PIN to test the device works perfectly. I imagine (and understand, somehow) the’ll ask for it when replacing the battery. Therefore I’ll wipe it.
Work will be done by a third party shop, because 1) It’s an old device, so I don’t care if it’s a third party battery 2) do do net require making an appointment, just show up and collect an hour later. Apple authorised shops require an appointment week(s) upfront.