One way that Tolkien considered dealing with the "Orc problem" was to eliminate them having souls altogether. From the "Myths Transformed" section of Morgoth's Ring:
Yes, it is true that one does not find such soulless creatures in man-like form in the real world. But it is equally true that one does not find immortal man-like creatures of great beauty and wisdom in the real world either.In summary: I think it must be assumed that 'talking is not necessarily the sign of the possession of a 'rational soul' or fëa. The Orcs were beasts of humanized shape (to mock Men and Elves) deliberately perverted/converted into a more close resemblance to Men. Their 'talking' was really reeling off 'records' set in them by Melkor. Even their rebellious critical words -- he knew about them. Melkor taught them speech and as they bred they inherited this; and they had just as much independence as have, say, dogs or horse of their human masters. This talking was largely echoic (cf. parrots). In The Lord of the Rings Sauron is said to have devised a language for them.
The same sort of thing may be said of Huan and the Eagles: they were taught language by the Valar, and raised to a higher level but they still had no fëar.