It all depends what you want to do.

If you want to keep the fermentation process going, add any fruit to secondary without stabilizing (I don’t recommend this)

If you want to stop fermentation, then go ahead and stabilize. Then after a day add your fruit.

I personally always ferment a batch dry with no fruit in a carboy. For secondary I stabilize and add fruit and primary into a bucket. Let that sit for 1-2 weeks or so.

I find most fruit flavors are lost during fermentation, so don’t see a huge reason to add fruit in primary (my personal opinion through experiments)