What is the ruling on paying a monthly sum to a local company that invests it in permissible global company shares, in exchange for receiving a sum of money later, with the aim of hedging against inflation?

It is permissible to invest in companies on the condition that the money is invested in activities that are not forbidden (haram), and that the capital is not guaranteed, meaning that the share is subject to profit and loss. It is also a condition to specify the percentage of profits at the time of contracting, such as 12% of the company's profits. However, specifying the profit beforehand based on the paid-in capital, such as telling you 12% in addition to what you paid, this is a usurious loan contract and it is not permissible to enter into it.