This is neither necessary nor sufficient for European improvement. In fact, a willingness to do this would imply that the Europeans had overcome the biggest thing holding them back: a lack of investment. If they were willing to pay for a program like this then they would be willing to pay for the sorts of youth programs and team infrastructure that could overcome the gap without such a program.
And that's the thing: the persistence of the gap between the North Americans and the Europeans is almost entirely a product of the different levels of investment the countries involved. Until the Europeans decide that they really want to close the gap, nothing anyone else does is going to make a difference. Throwing out ideas for what could be done is petty much irrelevant until they make that commitment.
Beyond that, I don't think that efforts at the adult level are really where the focus should be. The Europeans don't need tactical advice, or nutrition, or anything else with running an Olympic team per se. They need to have more young girls playing the game and getting youth level coaching. Until they start producing more potential Olympic players, nothing they do with the ones they have is a difference maker.