Yes, you remind me one important thing. Ligand is our second concern when we determine whether the system is of high spin or low spin.
For high-spin d6 system, it is really an inert species.
In your case, since all ligands are weak field ligand, low CFSE, low 10Dq, hence, it is low-spin d6 system.
The resulting complex becomes labile (undergoes associative or dissociative pathway more readily). It does find some ways to obtain d5 system, coordinatively inert system.