far off, distant, long ago
遙 centers on great separation in space or time: something far off, distant, or long ago.
遙 combines ⻌ (movement) with 䍃, which likely contributes the sound and possibly the idea of distance. The exact historical development of 䍃 is uncertain.
The movement radical ⻌ suggests traveling a long road, while the right side 䍃 looks like a distant hill with a setting sun 夕 over a container 缶. Together they picture a journey to a far-off place.
For ヨウ, imagine a distant yo-yo spinning at the end of a long string: yo-yo -> ヨウ, and the yo-yo is far off.