Is it permissible to use funds collected for building a mosque in Japan to purchase land designated as a cemetery for Muslims, given the impossibility of completing the mosque project and the urgent need for Muslim burial grounds there?

The money collected for building a mosque, if that becomes impossible, should first be used to build a mosque in another needy location, as this is the preferred option, considering the intention of the donors. If that is not possible, and there is an urgent need to purchase land for a cemetery for Muslim deceased, then there is no harm in doing so, based on the opinion of some scholars who permit changing the condition of an endowment (waqf) for what is more beneficial and advantageous. As for mosques built by others than prophets, the matter follows what is beneficial. So, if building a mosque becomes impossible, or if purchasing a cemetery is more beneficial due to extreme necessity, then it is permissible, especially given the fear of the money being lost, and because the donor's primary aim is often to gain more reward.