This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
劷 combines 羊 (sheep) and 力 (power/strength). The exact historical development is uncertain, and no clear meaning is recorded.
The kanji visually contains 羊 (sheep) and 力 (power). Picture a sheep with surprising strength, but its actual meaning is unclear.
For ヨウ, imagine a sheep (羊) using its power (力) to yell 'YO!' — YO -> ヨウ.