Can we get different cooling effect by same compresser & same expension valve by charging different Kg of same ref, but changing in Evep & Cond Coil?

both ideas wouldn't change the cooling effect much for the designed coolig capacity of the circuit

increasing the quantity of the refrigerator would be limited to the maximum load of the compressor and the expansion valve, also changing the evaporator and the condenser wouldn't increase the capacity until you change the compressor and the valve also to fit with the new cooling system

so both ideas would still restrict the cooling capacity for the designed capacities and the maximum you can get is the maximum of the designed capacity

sure we can but it must under certain regulation

YES