Tolkien's Orcs have language, and different personalities and are intelligent enough to make weapons/armor and other crafts. They're people. They have some kind of free will.
Then use magical wolves or some other type of unintelligent wild predator. Or something like Warforged. Or make the robots biological robots (like
@Oofta's version, where they're clones programmed to follow certain orders). Or give them some other justification for being hostile than just "they're born evil". Maybe they're like Thri-Kreen or Lizardfolk and enjoy eating the flesh of one of the other races. Or need to fight for some reason, like 40k's Orks. Or it's just a specific culture/religion/nation in the species that makes them "evil".
There is no justification for having an always-evil
race of mooks (that are people) be used as mooks other than tradition and nostalgia. There are better solutions. There are workarounds for using them other than making them people.