The minor error here is that wire fraud isn't literally named after crossing jurisdictions; there's nothing stopping a wire from having both its endpoints in the same state.

The major error is that while you're correct that wire fraud has to cross jurisdictions because of certain legal boondoggles, it isn't a crime in any of the jurisdictions it crosses. Only in the ur-jurisdiction superior to both of them.

Ignoring US peculiarity here, if you commit fraud online against someone from one country, when you're in a country where that is not fraud, that's something that would need to rely on extradition treaties. You haven't committed a crime at home where you were so police aren't going to come and arrest you unless the country you committed the crime against convinces them to do so.