Sharp seems reasonable, but I've never heard someone use it to describe garlic in isolation. I've only heard people use it when describing garlic flavor as part of a dish eg. "This pasta has a sharp garlic flavor".
Fresh raw garlic really burns, and I think it's quite normal to describe it as hot or spicy in American English.
Come on. You could at least read my comments before responding to them.
https://news.ycombinator.com/item?id=32111461
You really think "sharp" is a bad descriptor for raw garlic?