Might work, but personally I would prefer if they do something else than the high fantasy setting with every VS event.
We already had Yasuo VS Riven, both representing higher beings as an angel and a demon.
Then we had Darius VS Garen, again higher beings as "god kings".
So I would prefer not to go for 2 mages (thematically). It seems that the time line went on (Darius and Garen happened long time after Yasuo and Riven in the world lore), so I would do this again and jump more in the future, letting 2 cities with highly advanced technology fight each other.
Best candidates for this would be these 2 iconic rivals:
VS 
Both would mesh really well with the Order and Chaos thematic, too. Jayce is a self righteous jerk, who thinks he is preserving Order.
Viktor is seen as the "villain bringing chaos", yet he actually just wants technology to progress unbound and grant everyone a better life.