Perhaps I can respond not precisely to your question but to something that I think is relevant to this.
We speak about constraints and costs as though there's a bit of a veneer on this, like it's an additional burden or something to do this gender budgeting. I don't think we've sufficiently emphasized the potential benefits of doing this.
You stand to design policies that are much better designed to meet their desired objectives because you've taken into account the gender landscape in which these policies have to exist. It's like this: you could hire an architect to design a house, and that architect might do a quite capable technical job, but unless they go there and see things--was there a hill, was there a drainage problem, was there erosion--they don't make the plans in full awareness of the actual obstacles on the ground.
If you take into account the obstacles on the ground in terms of the issues around gender in society, then you can make a much more elegant response to the problems that you say you want to address. You say you want to address poverty or something like that. Great--then you'll make a policy that takes into account the fact that women who live in poverty have specific difficulties that need to be addressed if the policy is going to work.