The Dexibell closest to the CP73/CP88 would be the S3Pro/S7Pro, i.e. hammer action piano-centric boards (also similar in having more effects banks and 4-zone MIDI control). The Dexibell and Yamaha have a kind of opposite way of working in terms of mixing and matching sounds on the fly, though... on the Yamaha, you go to the sound you want, and then assign it to the keyboard section you want it on (left, right, or both), whereas on the Dexibell I believe you first pick the keyboard section you want (main, coupled, lower) and then assign the sound you want to it. Similarly, on the Yamaha, you assign effects to sounds, whereas on the Dexibell you assign effects to keyboard sections. Either approach obviously can work, but you come at them from a slightly different mind set. The Nord Electro 5 also worked the way Dexibell does, as do the Roland VR09/VR730 (kind of), while the Electro 6 and Nord Stage and Nord Piano models along with the Kawai MP11/11SE work more the way the Yamaha does.
As an aside, if it's for home use and portability is not a factor, I think the Kawai MP11SE could be a very viable alternative to a CP88... very similar design in many ways, and arguably offering a better piano/EP experience. It does weigh over 70 lbs, though.