MTG Salvation

Wondering if one could use Thespian's Stage to copy Emeria, the Sky Ruin and return two creatures to the battlefield per upkeep?

You essentially just have 2 Emerias and there is nothing against having 2 (or more) copies of Emeria. As long as you have 7 Plains, both with trigger. The only thing you can't do here is copy Emeria in the upkeep and expect to get the second trigger that turn. It won't trigger until your next Upkeep.

Thanks, just making sure.

Copy that

Nothing in your scenario is a Sliver so no. Is there some reason you think it would apply here?

Sorry. Should have added these cards are in a sliver deck.

Well Crystaline Sliver only grants shroud to Slivers that are on the battlefield, if that is what you are meaning.
So yes you can still return Sliver creature cards from your graveyard to the battlefield with Emeria's ability.

thank you