Contrary to popular belief tracing over models is more, not less time consuming. It just gives you more accuracy in proportions, perspective and keeping sizes constant. But you also have to take more time by perfectly following your reference instead of just drawing a frame without having to perfectly match a model.
KOF XII/XIII sprites took insane amounts of time per character, more than a year IIRC, while you can have a character animated in 4-5 months using traditional methods. It makes things look nicer (BBs sprites are definitely a step up from GGs wonky sprites and animations) but doesn't really save time.