The previous Season 2 episodes were mostly very good to brilliant. The season did start unevenly with "The Phantom, The Dog and the Hot Hot Sauce", but the next three episodes were incredibly well done. Especially "The Last Inmate", which gets my vote as the best 'Scooby Doo and Guess Who' episode. "The Hot Dog Dog" didn't really do an awful lot for me on first watch, great villain and some nice humour but the story and the guest star (here Joey Chestnut) were bland.
Rewatching "The Hot Dog Dog", my feelings are still rather lukewarm. There are still things that the episode does well, but it is very like "The Phantom, The Dog and the Hot Hot Sauce" in that it felt very bland and forgettable. A couple of the worst done aspects being really important. A real step down after being so impressed by the previous three 'Scooby Doo and Guess Who' outings, and as far as the show's episodes go it is in the lesser half while not one of the very worst.
Of course there are good things. The animation generally is vibrant, slick and atmospheric in one of the best looking Scooby Doo incarnations. The villain especially looks great, with a very cool design. The music has some nice groove and atmosphere and do like the nostalgic if too brief take on the iconic theme song when talking about the show in general. The voice acting on the whole is fine.
Moreover, there were some nice jokes. The best ones being with the Scooby and Shaggy shaped shrubs and Chestnut's observation about the celebrity introduction, the one time he shone in the episode. The best aspect is the villain, very cool looking and suitably eerie and entertaining with enough originality. The reveal at least wasn't too over obvious.
Chestnut however feels too much like a side character rather than a guest star, it was like the show was trying to take on board criticisms of the previous season having over-dominant guest stars and went too far the other way with him. Which really surprised me considering how much of an impression Morgan Freeman left on viewers just three episodes before. His personality is also very toned down and a case of him being just there. Most of the gang here are too dumbed down, especially Velma, and are not always used well. Shaggy and Scooby excepted, they were nailed although Scooby's song was a little on the disturbing side.
Furthermore, the mystery itself is every bit as vanilla and unmemorable as Chestnut and also feels too short with a very over-stretched second half. Which made for some rather dull pacing. While most of the voice acting is fine, Kate Micucci overdoes it as Velma, which was a frequent issue for me with this show and her casting has garnered a lot of criticism with fans.
Summing up, watchable but not an awful lot stands out. 5/10.