About six years ago, I planted two traditional loquat trees that my sister-in-law gave me from her yard. They look beautiful, have grown to about 12' in height BUT still bear no fruit. Why not?
Some some trees are more reluctant to bear fruit than others. If you are concerned about them, add fertilizers high in phosphorus and potassium to it. This article will help: https://www.gardeningknowhow.com/edible/fruits/loquat/growing-loquat-fruit.htm