I might have missed the issue at stake here but:
there is no problem using a single IB account to wire money in and out of different countries or continents. IB is the cheapest way I know to exchange currency and as it offers local funding methods in each currency it uses and it is often a great way to wire money between oone's accounts. Foe instance one should be able to wire CAD from Canada to Euro in some European country and only suffer the cost of the eurcad transaction on IB platform, which is cheap. Wire transfers on both sides should cost nothing.
Yet trying to open different accounts from different places adds more risks besides those already mentioned. IB might end up not recognizing the w8ben form in at least one of the accounts, which than gets hit by back up withholding tax. Ime IB doesn't t even bother to warn you the w8ben is no longer accepted, which can become very costly. Ime as well once the issue is fixed IB can reverse the tax, but the issue must be settled before. If u fill 2 application forms indicating different residencies it screams for problems.