I use andOTP on Android and it has a backup feature that exports all your registered 2FAs into a file which you can import to another andOTP install. You can also export with a password on that file so it's encrypted.

Other 2FA apps have backup options like Google Authenticator or Microsoft Authenticator. Bitwarden, if you pay for premium, gives 2FA as a feature and they just handle those codes. Just don't register Bitwarden 2FA under itself :D