[GNC] How to handle recurring transactions with currency conversion

[rsbrux]

We receive monthly payments from U.S. Social Security. These werre 
previously paid out in U.S. dollars (USD) but are now paid out in Swiss 
Francs (CHF).

I previously handled these with a scheduled transaction, since the 
amounts remained the same over at least a year, but this doesn't work 
anymore.

Since the income account is in USD, each deposit (to a CHF account) is 
now associated with a currency conversion rate determined ad hoc by the 
U.S. Social Security Administration.

Is there an elegant way to handle this, perhaps with a scheduled 
transaction having a constant USD amount and prompting for a conversion 
foctor, or should I just give up and create a corresponding income 
account in CHF and enter the transactions manually?

Is there an alternative solution that I haven't thought of?

Thanks in advance for any tips!