In the event of a Muslim's death in a foreign country, can Islamic Sharia be applied in the distribution of the inheritance if there is a will for the brother, and in the absence of agreement among the heirs, is it permissible to apply the law of the country where the properties are located?

A Muslim must apply God's law in dividing inheritances, and it is not permissible to reject that. The heirs must submit to God's حكم (judgment). If they are compelled to litigate in Western countries, let it be in Islamic centers or organizations, and let them not resort to man-made courts. A will made by the deceased to his heir brother is not permissible unless the other heirs approve it, due to the Prophet (peace and blessings be upon him) saying: "There is no will for an heir." However, if the brother is not an heir (i.e., disinherited by a closer heir), a will for him is permissible within the limit of one-third, and it must be executed before the division of the inheritance.