Currency swap - which currency SFR do you pay?

So this question came from the mock exam and the guy setting the question was drunk while setting the question/answer. The answer said that we should pay EUR SFR but proceeded to calculate SFR using HKD PV factor.The question goes like this:

If I were to borrow HKD and enter into a EUR swap, which currency SFR do I pay?

Thanks in advance.