Kann eine Passphrase das Risiko ausschließen, dass eine Hardware-Wallet eine vorher festgelegte Wiederherstellungs-/Seed-Phrase erzeugt?

Not sure where you got your information. The 25th word (passphrase) can only be 50 characters long.
“A passphrase can be any word, phrase, any set of letters, or even a sentence, up to 50 characters long.”
“A passphrase, as implemented in Trezor devices, can be any character or set of characters, a word, or a sentence up to 50 bytes long (~50 ASCII characters). Passphrases are case-sensitive – lowercase and uppercase characters are distinguished and count as different.”

https://wiki.trezor.io/Passphrase

https://blog.trezor.io/passphrase-the-ultimate-protection-for-your-accounts-3a311990925b

Still it’s a good idea to use pass-phrases.

As long as you make sure the passphrase is actually in use, then yes. You would have to enter the seed into something like iancoleman site, add the passphrase, and check that the addresses match. Do this a couple times with new seeds, and it’s unlikely that anything evil kicks in later.

(The hardware could be using, e.g., the first 4 bytes of the hash of the passphrase, instead of the passphrase itself. Good enough so that every different passphrase that you use will give you a different wallet, but trivial to brute-force for the attacker.)

100 characters would be sifficient entropy yes, however why not get arround this by simply rolling the dice?

https://shiftcrypto.ch/blog/roll-the-dice-generate-your-own-seed/

When was the last time you heared about pre-determined seed phrases with Trezor? If such a thing exists at all.

Just wondering.

If you don’t want to trust the seed generation then a passphrase can work well for this. Just pick a few words from the EFF diceware short list and you are good to go. (I talk about this in a video here https://youtu.be/nhjq_1J0EbU)

Just be sure to include the passphrase in your backups.

YES!

A passphrase can’t eliminate the risk, but it can reduce it by the amount of entropy in the passphrase (ignoring other possible attacks).

> Will a passphrase eliminate this risk?

No

The „keyspace“ of a 12 word passphrase is 2^(128), only a passphrase with a keyspace of 2^(128) will offer comparable protection. Since most passphrases are not complex enough to exceed this keyspace, „a passphrase“ will not eliminate the risk. Only „a sufficiently complex passphrase“ will.

A much better solution is [bip39-diceware](https://www.reddit.com/r/Bitcoin/comments/liwe2f/howto_bip39_diceware_creation/). Basically you roll dice to generated BIP39-words, then you try 16 combinations until you find one that meets the checksum requirement. It’s a horrendous amount of work, but it takes Trezor completely out of the loop.