«زَيْدٌ طَوِيلٌ وَعَمْرٌو قَصِيرٌ»
Zayd is tall, and ʿAmr is short.
Tall and short are contrasting values of the same characteristic. If the discourse compares two people, this contrast may supply the unifying relation needed for wāw: the clauses jointly describe a meaningful opposition.
Nevertheless, a lexical contrast is not an automatic license to coordinate anything. The people and their descriptions must form part of a relevant communicative purpose. A rhetorical jāmiʿ is assessed in context, not by matching dictionary labels alone.