What is the rule (assuming there is one) specifying which day count convention should prevail in a cross-currency swap?
For example, where EUR follows ACT/360 and GBP follows ACT/365, which of the two conventions would apply to the calculation of a EURGBP forward price?
Bloomberg DES function refuses to show a Day Count when called on a cross-currency ticker. I struggle to find a definitive answer, and as we're dealing with OTC markets here, I'm curious about the possibility of a counterparty requesting a different day count.
Thank you,
EDIT: Having tried SWPM as suggested made me realize my question is probably not narrow enough, in my initial bid to attract answers. The SWPM does leave it to the user to pick the Day Count.
So here is my exact business case instead:
A Gold forward is priced using simple interest (no coupon, no compounding, not matter how many years it might span): $$Forward = Spot \times (1+r_{swap} \times \frac{ACT}{DayCountConv})$$ with the swap rate (GoFo) defined as the difference between the USD rate (Libor or SOFR nowadays) and the Gold rate (aka "lease rate") $r_{GoFo} = r_{USD} - r_{Lease}$
With Gold and USD both using a 360 daycount convention, all is well.
But is there a rule when pricing, say Gold in GBP or AUD, where both those currencies conventions are ACT/365 ?
Thanks again,