The given complex is $[\text{Co}(\text{NH}_3)_4(\text{NO}_2)_2]\text{Cl}$.

1. It contains the ambidentate ligand $\text{NO}_2^-$, which can coordinate through either the nitrogen atom or the oxygen atom. Therefore, it shows linkage isomerism.
2. The counter ion $\text{Cl}^-$ can exchange with the ligand $\text{NO}_2^-$ to form $[\text{Co}(\text{NH}_3)_4(\text{NO}_2)\text{Cl}]\text{NO}_2$. Thus, it exhibits ionisation isomerism.
3. It is an octahedral complex of the type $[Ma_4b_2]$, which exists in two geometrical isomeric forms: cis and trans.
4. It does not exhibit optical isomerism because both its cis and trans forms possess a plane of symmetry and are optically inactive.