Can the card Creature Swap be used if you have no monsters on field but your opponent does and do get to keep Hisher Monster for rest of duel in Yu-Gi-Oh?

You are correct! Creature Swap can be activated even if you have no monsters on the field, as long as your opponent does.

Here's the breakdown:

* Creature Swap's effect: "Target 1 monster you control; take control of 1 monster your opponent controls until the end of this turn. You cannot activate this card the turn you activate this effect."

* Key points:

* It targets 1 monster you control. This means you don't need to control a monster for the effect to activate.

* It then takes control of 1 monster your opponent controls. This means you do need your opponent to control a monster.

The catch: You only control the opponent's monster until the end of the turn. Once that turn is over, the opponent regains control of their monster.

So, to answer your question directly:

* You can use Creature Swap in the scenario you described.

* You won't keep your opponent's monster for the rest of the duel.

Let me know if you have any other Yu-Gi-Oh! card questions!