The Belt and Road Initiative is an economic integration plan. But at regional level, the financial capabilities of route countries do not allow the implementation of the Belt and Road. This is the need for and creation of a new financial form. This study aims to theoretically justify a new financial form for economic integration—new type of over-the-counter derivative financial instrument. This adaptation addresses the case of the transport corridor ‘China–Mongolia–Russia’ and ‘resident status’ of the Joint Economic Zone that will serve as a guarantee for the financial assets of the Belt and Road companies and increase their financial sustainability and investment revival in regions. In general, this has a positive effect on the development of the accounting system and increases the financial and investment interests of business participants, which can lead to new forms of entrepreneurial activity and become a catalyst for improving the welfare of regions of China–Mongolia–Russia transport corridor, and it is in line with the goals and investment initiatives of the Belt and Road project.