Transaction usdc -》Ether

https://etherscan.io/tx/0xe7b3c9ed21d747c136f1f2caec92e4879dcbe225d0d0c6aefd0fb09762ba9cfb

Why does the transaction take so long?

Because you set extremely low fee 0.000000009 Ether (9 Gwei).

When making transactions, sufficient fees must be set. Seemingly, your tx was not the case. However, the computation has to be paid, regardless of whether transaction succeeds or fails. The computation is paid even if the transaction fails because the miners must validate and execute the transaction (compute). Please, keep in mind, fee is paid to miners, not to Trezor.

The latest version of Trezor Suite enables you to set custom fees. Please, make sure you are running the latest version.

Once installed, you can easily customize both gas price and gas limit. See as pictured.

The first one is the Gas limit. The gas limit refers to the maximum amount of gas user is willing to spend on a particular transaction. Higher gas limits mean that more computational work must be done to execute the smart contract. A standard ETH transfer requires a gas limit of 21,000 units of gas.

The second field is the Gas price and it is up to you what gas price you will set. The higher the gas price, the higher the transaction fee, but the shorter time to get your transaction confirmed. To have some idea what gas price you should set, have a look at ETH Gas Station https://ethgasstation.info/ or Gas Now https://www.gasnow.org/

Trezor Suite https://suite.trezor.io/ now enables to speed up an Ethereum transaction by increasing gas fees. Learn more from our blog post if you like https://blog.trezor.io/trezor-suite-updates-march-2021-622badf227f2