similar
仵 centers on the idea of similarity or equivalence: being alike, matching, or corresponding to something else.
仵 combines 亻 (person) with 午, which likely contributes the sound. The exact historical development is uncertain, but the character is used to express similarity or matching.
A person 亻 standing beside 午 (noon) suggests two things aligned at the same point, like a person matching the time. Think of two similar things meeting.
For コ, imagine two similar-looking children (子, こ) standing side by side: 子 -> コ, and their similarity matches the meaning of 仵.