Most likely western tanks would be used in the rear to free up soviet designs to fight in the front. This has the effect of PR, less chance of losing them and much shorter supply lines for the complicated maintenance machines.Going that ways means no more Soviet design available. Strange after and article that Ukraine have more tanks than at the start of the war...
If they do so, they need to put all these in the same unit to have a designated logistic chain for ammo and parts. They cannot spice the front with a small quantity like that. They will need to put them all together.
Adding up Leopard 2 bring the same problems, it don't have the same gun and motive parts too, so if they receive them it would be another designated unit.
If they don't build designated unit it will be hard on logistic for sure.
If the West ever supply enough tanks to form a solid fighting force, It would then make sense for them to form delicated units of western tanks for larger scale offensive manuveres.