does the following sentence sounds reasonable?

It should be like this:

This agreement has two versions, one Chinese and the other is English. The two versions share the same legal validity.

Write it like this:

This Agreement has two versions, one is Chinese, the other is English. Both are legally valid.

or

This Agreement has two versions, one is Chinese, the other English and they have the same legal validity.

"both of the two" is a tautology. Your sentence should read:

This Agreement has two versions, one in Chinese and one in English. Both versions have the same legal status.

both parties have reviewed the translation in their respective language? In the event of a dispute the [Mandarin]/[English] version shall control. Also where is the dispute to take place? In what language? Whose law controls?

Hi,

The sentence reminds me of someone hollering in a canyon; which way is it coming from?

You do not need "of the two" peace.