0593 Jellicent

Both fast moves are similar in performance; Bubble offers slightly stronger Water-type coverage, while Hex sports slightly faster energy gains with Ghost-type coverage. Either moveset can be viable.

Surf is Jellicent's cheapest Charged Attack and has solid DPE, allowing Jellicent to deal consistent Water-type damage. Shadow Ball benefits from STAB to deal significant damage, which is largely unresisted against most of the meta. Ice Beam offers useful coverage, including against Jellicent's weakness to Grass-types, but its damage output is less impressive. Bubble Beam can be used to debuff opponents, but it is generally too weak.

Jellicent is a unique Water/Ghost Pokemon with good bulk and a versatile moveset. While its typing doesn't synergize well to cover their weaknesses, they do provide Jellicent with a long list of 8 useful resistances. Its success against various meta picks including Azumarill is notable, and also challenges various other Water-types due to its resistances to both Water and Ice-type attacks. Overall a very strong contender in the meta that's worth the resource investment. Be wary of its struggles vs Dark-type Pokemon, Noctowl, Lickitung, and Lanturn, however.

Jellicent is incredibly powerful in both open Ultra League and Premier Cup formats. With strong neutral coverage that's largely unresisted, in addition to its useful resistances, Jellicent stands to challenge much of the meta in a big way. Only a handful of Pokemon can comfortably beat Jellicent, including Snorlax, Alolan Muk, Gengar, and various Grass-types. Hex is recommended for Ultra League, though Bubble helps flip the matchup vs Obstagoon. Overall a very strong pick, with the biggest drawback being the amount of XL candy needed. 

Jellicent lacks stats for Master League, with few wins most notably against Metagross and Fighting-types.