Quoting myself just in case you missed
There is a pretty strict logic in the game about stats, elements and status effects which makes me 99% sure evasion down is ice based. Anyway it's very easy to test on fire/ice elementals... if you see the added effect never procs then it's definitely ice.Eva down = ice and defense down = wind.
If it's not that then I must say I'd be surprised, though it would be really interesting.