There are a few Pokémon both answers neglect that I think fulfill this criteria well, of which are:
Golett and Golurk, who are both the Automaton Pokémon, created from clay by an ancient civilization to protect and serve both people and other Pokémon.
Magearna, the Artifical Pokémon, created by a scientist as a gift to royalty, specifically to a king's daughter 500 years ago.
Iron Hands, theorized to be a cyborg modified from an athlete who was mortally wounded. Much like the rest of the Paradox Pokémon's dex entries, this is left unproven.
Iron Valiant, likely resembling a human most out of the list. It's theorized to be a robot created by a mad scientist from the future.
Source