Flashing will overwrite the whole device, does not matter what partitions or format is there before.
As long as you can select it in balenaEtcher it is good to go.
Let me know if you need more help.
Thank you for letting us know. I agree, disabling Windows Defender is not a great solution and we should be able to do better than that. The Windows settings “Controlled Folder Access”, “Focus Assist” and “Ransomware protection” are known to interfere with Etcher activity. Can you review the suggestions in this issue and let us know if they allow you to otherwise enable Windows Defender?