Chrimson Angel, it may well be that Rumple and Regina will eventually be on Snow’s side but that doesn’t mean Emma and Henry would trust either of them. For all we know, neither Regina nor Gold want Cora (and probably Hook) in SB so they may have good reasons to convince the Charmings about it and they may unite against those other villains (I also have a feeling king George hasn’t said his last word yet) but almost certainly they will have their own hidden agendas and won’t hesitate to act on them and Emma surely knows that – so yes, I expect a pact but only a temporary one.