No that is not the case here. I am talking about a Trezor passphrase. I mean that I try to recover the account using the Trezor, and the Trezor wallet that I used to create the account has a passphrase, the “25th word” just as you say. I am not asked to enter any seed phrase anywhere. It just redirects to the Trezor webpage where I allow it to share the public key, and enter the passphrase. This is the same whether I try to restore the account, or perform an action (send or claim rewards, for example).
(And yes, I only enter the passphrase on the Trezor hardware itself, not in any software wallet).