Although i voted Water, Poison seems to be a great choice here. There are a lot of way to prevent Earthquakes without Levitate, like Magnet rise, Imprison, ect. But the thing is, they're not as reliable. We have to be sure its weakness won't hamper it, and even if alternative options are present, we'll lose a move slot and that's not good.
That being said, if Water/Electric is chosen, we'll have to make it the most different possible from Lanturn. We could make a Speedy and frail Counter (which would look a bit like Starmie), or a fast and defensive pokemon. For that, I would recommend a balance of abilities, such as a more offensively inclined one (like motor drive or an Electric Flash Fire) and a more defensively inclined one (for example Volt absorb or Levitate), which would make it able to handle a lot of threats, but not all of them at once (which was the primary concept of CAP 10).
Also, I voted Water because of a lot of useful resistances and few weaknesses, allowing lot of switch-ins and easy countering with useful STABs.
That being said, if Water/Electric is chosen, we'll have to make it the most different possible from Lanturn. We could make a Speedy and frail Counter (which would look a bit like Starmie), or a fast and defensive pokemon. For that, I would recommend a balance of abilities, such as a more offensively inclined one (like motor drive or an Electric Flash Fire) and a more defensively inclined one (for example Volt absorb or Levitate), which would make it able to handle a lot of threats, but not all of them at once (which was the primary concept of CAP 10).
Also, I voted Water because of a lot of useful resistances and few weaknesses, allowing lot of switch-ins and easy countering with useful STABs.