Rules FAQ

• If Shrewd Diplomat enters play as the result of a reaction to winning or losing (e.g. The Queen of Thorns TMOW), it can stand and remove a participating character without affecting the winner of the challenge or the amount by which the challenge was won.
• The above can also cause a character to be participating alone, similar to e.g. The Hound and Mirri. For example, if you win an intrigue challenge with Queen of Thorns (4 str) and Mirri Maz Duur (5 str) which is defended by a House Maester (2 str), then trigger Queen of Thorns to put Shrewd Diplomat into play, you can stand and remove Queen of Thorns from the challenge, trigger any win by 5 effects (e.g. A Pinch of Powder), and trigger Mirri Maz Duur’s interrupt.

As you can see, this artwork isn't the Queen of Thorns, but instead a shrewd diplomat in her seasoned years. Possessing a standard stand and remove ability for Tyrell, for the modest price of 5 gold, whichever way you look at it. 10/10 for NOT Queen of Thorns.