The top picks outside of lane to counter Blitzcrank include Caitlyn, Zeri, and Jinx. These champions are all great at countering Blitzcrank with high win rates over 55%. Even if these Blitzcrank counter picks are not picked in your lane, it's not smart to play him into any of these matchups. They will usually destroy Blitzcrank.
Yet, if the opposite team brings either Ziggs or Kennen, you should seriously consider taking him, as he easily dominates these champs with win rates over 52% against both ofthem.