KitchenAid
KitchenAid isn't chasing plastic-free, but the stand mixer is mostly metal where it counts: a stainless bowl and bare-metal dough hook and whisk. The one food-contact plastic-ish weak point is the default flat beater's polyester-powder coating over aluminum, which can chip into food over time. Usefully, they sell bare burnished-aluminum and stainless beaters as swaps, so the coated part is avoidable rather than baked in.
How clear are their specs?
Materials are named specifically - stainless bowl, burnished aluminum and stainless beaters, and the default beater's polyester powder coating over aluminum - so you can tell exactly what each part is.