pretend, feign, false, deceitful
佯 centers on deceptive behavior: pretending, feigning, or acting in a false and deceitful way.
佯 combines 亻 (person) with 羊, which likely contributes the sound and may relate to the idea of a sheep's gentle or deceptive appearance. The exact historical development is uncertain.
A person 亻 beside a sheep 羊: imagine someone putting on a sheep's innocent face to pretend they are harmless, when they are actually being deceitful.
For ヨウ, picture a person pretending to be a sheep saying 'yo!' to blend in: 'yo' -> ヨウ, and the fake greeting reveals the deceit.