Hello divyanakra,
the current flowing into the low impedant pin 2 of the OpAmp will always be mirrored to node 5 of the simplified schematic in fig. 31 of the data sheet. So in your words: Iz will always follow Ix in magnitude and in sign (unless you drive the OPV beyond its limits).
Node 5 has an internal capacity of several pF, you may add external capacitor or a network at pin 5 to influence the frequency behaviour of the OpAmp. But the sign of the current through pin 5 should always follow the sign of the current through pin 2. In your words: you can not get Iz = -Ix.
I assume, that you want to use the AD844 in inverting and in non inverting configuration (this is how I read your statement: "Because i am using both configuration in my project work."). But the inverting or non-inverting configuration is not related to the sign of the current to node 5. The sign of the current depends on the direction in which the output of the OpAmp is changing: for a rising slope Iz (and Ix) have a different sign than for a falling slope. When the output voltage does not change, then Iz = 0.