Master Password Backup

Yeah I mean if you write it down then an attacker would need to a) get it b) know what it is and c) have the 2FA which is presumably enabled. I would just try and have a master passphrase you could remember. 5 or 6 words is secure. If you wanted, you could have your master passphrase stored an a kdbx keepass file, that only unlocks with a keyfile, and then keep 2 or 3 USB drives with the keepass file somewhere, with the keyfiles in seperate locations. I know for crypto wallets they have these bolts that you can put a phrase on and then drill it into concrete. You really can get very creative.