Just to answer my own question and might be useful for others to know.
Late last night I tried to transfer EUR (which I had already exchanged from HKD on IB) from my IB account (opened in HK) to my overseas account.
This afternoon it was already on my overseas account!! No charge from IB and very little charge from the bank (9 EUR)
So it seems this is the cheapest way to both do the FX and to transfer the money overseas to your own account!.