Is marketing for translation companies as a translator—with forgery in the CV and presenting the work of another translator to the company—considered unlawful (haram), and what is the ruling on the profits earned from that before the questioner became aware of its unlawfulness, and does he bear the sin of those whom he taught this practice?

There are two issues: First, it is permissible for an employee to hire another person to perform his work, unless the employer stipulated that the employee must perform the work himself, or if the work depended on the employee. Second, it is forbidden for the employee to deceive and lie and submit a forged CV, especially if it affects an increase in wages.

Regarding the money earned previously: If the translation met the conditions, then nothing is required of you, and you must repent from lying and forgery. As for those whom you taught that, you must advise them and explain the prohibition of lying and deception.