Two different cloud password-protected vaults, plus
Authy, which automatically backs-up account keys; recovery is fairly simple using a phone or a PC\tablet.
Stored in a double encrypted docx backed up everywhere. I do not trust in dedicated apps, their databases can get corrupted and then even a backup/sync restore might fail.
This is a good idea that @TairikuOkami mentioned. I forgot to say that I also keep copies in .csv format inside an encrypted container, disguised as a video in .avi format, using the steganography technique, that even if it falls into the wrong hands, it will still have the encryption after going through the steganography
1password has 2FA key handling, it generates and attaches the 2FA to the site profile. Recovery keys are stored in secure notes inside 1Password as well.