Is it permissible to slaughter the aqiqah sheep in two different countries and at two different times?

There is no harm in slaughtering the two sheep for the 'Aqiqah in separate places or in one place, especially if there is a legitimate benefit in doing so. As for the time of slaughter, it is best to do it on the seventh day; if that is not possible, then on the fourteenth, or the twenty-first, otherwise, at any time it becomes feasible.