Pretty self explanatory question, should we ever expect weekly event skins (not limited time ones like nano cola D.Va or Bastet Ana, I mean the ones like Fantasma Sombra from Halloween or Terracotta Baptiste from the just finished Year of the Ox event) to either return as challenges or as purchaseables when these events come back next time?
Anniversary apparently didn’t include them last year, so unless there are plans to change that, the next iteration of the event’s would be the only opportunity to acquire them now. 
Also it’s pretty weird that the ones you don’t have don’t even show up on the hero gallery even with all filters checked in.
As of this time, any rewards from weekly challenges from any seasonal event or limited-time promotion are not intended to return. Make sure to always check in when a new event is running to make sure you do not miss out.
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