If Stasis Snare leaves the battlefield before its triggered ability resolves, the target creature won’t be exiled.

Auras attached to the exiled creature will be put into their owners’ graveyards. Equipment attached to the exiled creature will become unattached and remain on the battlefield. Any counters on the exiled creature will cease to exist.

If a creature token is exiled, it ceases to exist. It won’t be returned to the battlefield.

The exiled card returns to the battlefield immediately after Stasis Snare leaves the battlefield. Nothing happens between the two events, including state-based actions.

In a multiplayer game, if Stasis Snare’s owner leaves the game, the exiled card will return to the battlefield. Because the one-shot effect that returns the card isn’t an ability that goes on the stack, it won’t cease to exist along with the leaving player’s spells and abilities on the stack.