The WoW TCG Tournament Policy Document doesn't mention foreign cards, but if it's like Yu-Gi-OH!, then you can use foreign cards as long as you have the English one at hand for reference.
Yu-Gi-OH! Official Tournament Policy Document:When using a card that is not in a local language, a local-language version of the card or an accurate card translation must be available outside of the Deck to show to any opponent. This will help ensure that both players understand exactly what the card does.
I would imagine it would work the same way in WoW TCG, but they'd need to update the Tournament Policy Document for WoW TCG first...
WoW TCG Judge LV2
Player Managment 2
WoW TCG RK2
Disclaimer: All answers provided assume that you have enough resources to exhaust, and are able to pay any other additional costs, in order to play the referenced allies/powers/abilities.