As of my knowledge cutoff in September 2021, the latest "Weird Al" Yankovic song release is "Now You Know," a parody of the Dua Lipa song "Don't Start Now," released in October 2020.
However, since my knowledge is limited to that date, it's possible that "Weird Al" has since released newer material. I recommend checking his official website, social media, or streaming platforms for more recent song releases.