What do you call these cold pickled cucumber skewers in Chinese?
冰鎮 =  chill with ice 

pickled cucumber = 腌黄瓜

The item in the picture could be called 冰鎮腌黄瓜 or simply 冰鎮黄瓜

Of course the seller can name it whatever he wants, for example '冰脆黄瓜串'