Possible to intercept and alter SQL Queries in the engine before it gets executed?
No, it is not possible to intercept and alter queries.

If somebody dangled millions of dollars in front of me to pull it off, I can imagine building a wire-compatible app that acted as if it was taking queries, then rewrite them and pass them off to another layer. However, that's not a small exercise, and it's left for the reader. This is the kind of thing GreenSQL (now Hexatier) was doing, sitting in between the apps and SQL Server, doing caching and auditing.