No it's not. よう is not the same as "Yu".
よう is closer to how you would say the exclamatory "Yo—!" (not exactly, but I'm too lazy to bust out IPA).
With the name being "陽", "You" is the same character as in the name "陽介" or "Yosuke"
First semester Japanese lesson:
The capital of Japan: 東京.
How...