No,it is not.No. There are many references that speak to bearing fruit; but it is the only reference that speaks to being known by the fruits.
1 John 4:1
Unless you insist upon the phrase itself being exact in scripture, "by their fruits you shall know them", there are many verses that identify the metaphor of fruits .
Matthew 12:33. “Either make the tree good and its fruit good, or make the tree bad and its fruit bad, for the tree is known by its fruit."