Is it considered contrary to Islamic Sharia to engage in fictitious subscriptions to foreign companies and profit from them, knowing that these companies require real subscribers?

If companies stipulate that the subscriber must be a real person, then it is not permissible to deceive them. And if subscribing to them entails falling into a Shariah-forbidden act or aiding in it, then it is also not permissible, and benefiting from the compensation is forbidden because it is a wage for a forbidden act. So, the deciding factor is the company's terms, its field of work, and what results from subscribing to it.