Walk through his shield, hook him closer to your teammates. In a 1v1 watch out for his turrets, try to stay out of their fire angles and you will out-dps him then with the help of your shell heal card and extra hooks.

As Barik, drop your Turrets and shield, play a cat and mouse game where youre the mouse, let the turrets do damage meanwhile and keep your shield or cover between you and the turtle.