The Adventures of Jimmy Neutron: Boy Genius - I kinda liked Hartman's take on the Jimmy Neutron cast

They made three specials with this crossover.

They were all so fantastic.

You just don't get crossovers like that anymore.

The thing about Goddard is that he is not a human character or actual animal. He is a robot dog with an unconventional design. My guess is that the drawing team did not quite know how to translate his design in FOP's style accurately like they with with the kids, so they went for special effects, instead.

That is actually a smart choice: better to do something half-assed but well done and functional than something original but completely lacking that does not work. Well, unless you study Computer Science and work with software, where we are told the exact opposite: better to give the client a shitty product that they asked for rather than something better they never asked for, because, for some odd reason, they bitch less about the former than the latter, and you definitely want to keep "client bitching" on top of the priority list of "Things to Avoid".