After creating a villager breeder in a plains biome, the villagers that were created have the pre-1.14 farmer/fisherman/fletcher/shepard texture and do not have biome specific traits, which in this case should be either plains (the biome they were created in) or desert (the biome that the parents came from). They also don't have any profession or trades, making them similar to the pre-1.2 villagers. The attached image shows these villagers.