You don't have to go all the way through those processes just to sign in to a message for security reasons so as not to visit the wrong site and give away your password just to generate a working private key.
Since you are a TrustWallet user, which was already not a regular recommended wallet,

If you are using a mobile device, you can download BlueWallet from your Play Store or App Store, and you can import your wallet using your wallet phrase. When doing that, select the Bitcoin option, and when the wallet has successfully been imported, You click on the imported wallet and are taken to the next page, where you can click on the 3 dot on the right top corner of the wallet, and you will see the sign-in message option among others.