🔼The name Evi in the Bible
There's only one man in the Bible with the name Evi. He is one of the five kings of Midian, whom Moses, Phinehas and the Israelite army defeated (Numbers 31:8). When Canaan was divided, the territories of these five kings befell the tribe of Reuben (Joshua 13:21). In that same war against Midian the famous oracle Balaam was killed.
🔼Etymology of the name Evi
There's no word אוי in the Hebrew of the Bible, but it seems obvious that the name Evi stems from any of the roots אוה ('wh):
Our name may be constructed from the noun או ('aw), meaning desire, and turned into an adjective by adding the letter י (yod). It may also be a regular noun, which existed but was never used in the Bible.
For a meaning of the name Evi, NOBSE Study Bible Name List reads the adjectival Desirous. Jones' Dictionary of Old Testament Proper Names proposes the noun Desire. BDB Theological Dictionary proposes the same noun Desire, but adds a question mark to indicate that we're all just guessing.