If I were you, I'd go with Ferroseed/Ferrothorn instead of Pawniard/Bisharp. For one, Pawniard evolves at level 52, which is really late, whereas Ferroseed evolves at level 40. Also, there are Water types that can give Zebstrika trouble (Seismitoad for example). Ferrothorn can deal with those just fine.
If you really need something against Psychic types, you can switch your Zebstrika for a Joltik or a Tynamo. Tynamo evolves into Eelektrik at level 39, which can learn Crunch, which can also help against Ghost types.