TRAPPIST-1e
In November 2018, researchers decided that of the seven exoplanets in the multi-planetary system, TRAPPIST-1e has the best chance of being an Earth-like ocean planet, and the one most worthy of further study related to habitability. What's more, according to the Habitable Exoplanets Catalog, TRAPPIST-1e is one of the most possible habitable exoplanets discovered.