Prior to the region soft lock update, it was possible to play with friends cross-region (Europe and Australia) on the Asia servers each at a playable ping of 100-120ms.
Returning back to Overwatch and finding out about this update meant playing between regions, like Europe-Australia, is no longer possible due to a player in one region suffering an unplayable 300-400ms, while the other has 20-30ms.
An announcement about the update states the following:
(Full post below)
While the average between one player in Australia, and another in Europe, is about 160ms-220ms, the reality is one of them currently sits on a ping of 400ms. A low average isn’t what made cross-region play possible, it was the middle-ground of each having about 100ms - Something that was achieved, in our case, by selecting ‘Asia’ as a region (and actually putting us both in those servers).