Is it permissible for a company to pay for an employee's visa costs, and then reduce their salary for a year without informing them that this reduction is in exchange for the visa costs, with the understanding that their salary will increase in the second year, under the pretext that the employee might not stay with the company for long?

Companies are permitted to employ workers at a lower salary in the first year, provided two conditions are met: First, both parties agree to the salary without coercion, based on the Almighty’s saying: "unless it be a trade by mutual consent." Second, there should not be a specific salary stipulated by the state that companies are obliged to pay these workers. If the state mandates a specific salary, then it is not permissible to diminish the worker’s right.