$$\Delta I=1/2$$ Δ I = 1 / 2 rule, $$\varepsilon '/\varepsilon $$ ε ′ / ε and $$K\rightarrow \pi \nu \bar{\nu }$$ K → π ν ν ¯ in $$Z^\prime (Z)$$ Z ′ ( Z ) and $$G^\prime $$ G ′ models with FCNC quark couplings