Last I've had to do this (last November): for Google itself, you need to set up SMS 2FA, and then you can add an additional TOTP device and remove the SMS 2FA.

Last I've had to do this (last November): for Google itself, you need to set up SMS 2FA, and then you can add an additional TOTP device and remove the SMS 2FA. A bit annoying, but worked for me for my work account.