First of all, it's not recommended to restore a hardware wallet's seed phrase to an online client because it defeats the purpose of using a hardware wallet where the keys are supposed to be kept offline.
Anyways;
-snip- Seed type: BIP39 seed -> OK -> type in seed, but 5th word of 4 letters offers 2 words, 7th word of 4 letters offers 3 words, 18th word of 4 letters offers 2 words, whereas Trezor would just select the single word from 4 letters?
Electrum just shows you the possible valid word that can be completed with those first four letters, it's not something to cause incompatibility.
-snip- Finish -> Balance: 0. mBTC.
Have you set a passphrase in Trezor?
If so, enable "
Extend this seed with custom words" in the options where you ticked "
BIP39 seed".
With that option enabled, you'll be asked for a passphrase after clicking the 'next' button.
-snip- Detect Existing Accounts -> BIP39 Recovery: No existing accounts found.
Since you already done that, I assume that you've actually typed your Trezor backup phrase to an online machine.
If you ever successfully restored your wallet, send all of its fund immediately to a new seed (
wallet) created by your Trezor.