Same here! But I think they might be reusing the same motors, so it should be fine. The Core One additionally includes a third Z-motor in the "Electronics & Chamber parts box". (Couldn't find a definitive source to back this up, since the Mk4S -> Core One conversion kit manual isn't available yet. At least they have the same specs, though if anything were to differ, it would be the lengths of the cables. I'll try to remember to update this comment to confirm whether it works once I finish assembly.)
@Prusa, changing the sticker to say both "MK4 motor kit (1/1)" and "Core One motor kit (1/2)" might be a good idea to prevent confusion :)
@Prusa, changing the sticker to say both "MK4 motor kit (1/1)" and "Core One motor kit (1/2)" might be a good idea to prevent confusion :)