Personally, I don't like this idea as a shard. The entire concept of a shard is that the unupgraded version does absolutely nothing but waste quanta, then becomes much greater as an upgraded card. Shards were also never known to favor elements of any sort, but used universally.
I'm no curator, but I hold a vote. If this were to be entered to the Crucible as is, it wouldn't have mine.
Possible improvements have been listed above. I see this as more of a permanent water card. It definitely fits into the water element in that it immobilizes a target for a temporary amount of time, yet is versatile in that it can switch targets as necessary. A cost of 3/2
to play the permanent, then 1
to use the effect seems reasonable, in my opinion. As for the name, Cold Heart fits well.
Other name suggestions:
-Cold Wind.
-Arctic Climate
-Frost
-Sleet Cannon