What is the ruling on money and profits earned from a new account opened on a freelancing platform, given that this violates the platform's terms which prohibit multiple accounts for a single person?

If opening the account violates the website's terms, then it is not permissible Islamically, based on the Prophet’s (PBUH) saying: "Muslims are bound by their conditions, except a condition that makes lawful what is unlawful, or makes unlawful what is lawful." As for the money earned from working with this account, it is not inherently forbidden.