The answer, John, is 'Yes!' There was one packaged with a Batman Beyond action figure, but that was the Ace of Batman Beyond continuity. There was also one packaged with a Golden Age Batgirl and Batwoman made by DC Direct. Then there was this one from the Krypto the Superdog cartoon. In fact, I believe there were a few versions of Ace the Bathound made back in 2006 for the Krypto the Superdog cartoon. The only one I picked up was this one, which also came with an 'Ace Racer' skate-type vehicle and Bud and Lou, Harley Quinn's Hyenas.
This was the only toy I picked up from the short lived Krypto the Superdog cartoon, but looking back, I wish I had grabbed them all. Or at least a Krypto! But if I recall correctly, the series had lots of cumbersome action features, and this specific set was just the figures, clean and simple. Which is how I like my action figures.
LEGO Ace the Bathound.