Can you play foreign language runes with an English deck/legend in tournament play?

Ruling: Foreign language runes can likely be played with an English deck/legend, but there is no official ruling yet.

Nuances:

• Decks can only include cards from one language, so if you include a foreign language card like a Chinese Ahri promo, the entire deck must be Chinese
• Runes appear to be treated differently than regular deck cards for language restrictions