Agree, may be difficult to get a final/complete answer on this forum since very few of us also own 530i's. I would expect a better/more definitive answer available on bimmerforums where other 530i drivers have fitted M5 wheels (or tried to).
That said, I'm pretty sure the answer is yes. They are both 5x120 bolt pattern and center bore 74.1 so the two biggest issues are clear. I know some (but not all) 540 wheels fit M5 because a number of M5 owners use then for winter duty; those that don't work, don't fit over M5 brakes).
The biggest issue I see is whether the width of the M5 wheels will be an issue, rubbing on either fender lip or inner liner. You may have to run 4 M5 fronts if the rears don't fit. Good luck.