And why is it necessary? If we can buy any furniture in the construction mode. It’s just an essentially useless feature.
However, there is a slightly different proposal that will be similar to this one, but will already have gameplay meaning. The part is described here Add famous game mechanics from The Sims 2 and 3 to InZoi.
As for this, it can be done, but only on one condition: if this furniture is exclusive, that is, it will be impossible to buy it in construction mode (at least for residential areas), then it will make gameplay sense.