Of the seven elements in Genshin Impact, the Cryo element offers a unique utility in that it can freeze water. In terms of elemental reactions, Cryo has powerful reactions with Electro, Hydro, and Pyro, making it very versatile and useful in many situations. At the moment, there are only four playable Cryo characters in the game, making it one of the least represented elements, but that is set to change in the near future as there are several upcoming and rumored Cryo characters that will be added in future updates.
There's a notable lack of diversity among Genshin Impact's Cryo Vision holders in terms of what weapons they use, with two of the available characters using swords and the other two using a claymore and a bow. At the moment there are no Cryo spear users and no Cryo catalyst users, but fans are excited to see characters with those combinations added eventually. Particularly the addition of a Cryo catalyst user would be very useful for exploration, as it would allow players to freeze and traverse over water much quicker. Beyond these four current characters, there are also at least two confirmed upcoming characters, one mentioned character that will likely become playable, and the potential for a Cryo Traveler.
Kaeya - Calvary Captain of the Knights of Favonius
Kaeya is the Calvary Captain of the Knights of Favonius, and one of the four free characters that all players get from the prologue of Genshin Impact. Despite this, his utility is undeniable, as his elemental skill is on such a short cooldown that he can apply the Cryo status effect quickly and even create ice bridges across expanses of water. As a free character, he isn't the most powerful option players can use, but his elemental burst does persist after switching characters so he is a good support. This is a great way to set up melt reactions with a Pyro main DPS like Diluc or Klee.
Chongyun - Banisher of Evil and Rumors Thereof
As an exorcist, Chongyun specializes in dealing with evil spirits, but he's never actually seen one. This is because his positive energy is so strong that they flee before he even arrives. From a gameplay perspective, he's a powerful Cryo claymore user that is more than capable as a primary DPS or as support. His ability to imbue normal attacks with Cryo sets him up as an amazing secondary DPS character, but his great stats and powerful talents allow for a more straightforward approach as well.
Diona - Wine-Industry Slayer
A bartender that hates alcohol, Diona's backstory is tragic and she is an interesting character to say the least. As a Cryo bow user, she has the unique capability of not relying on elemental skills to apply Cryo. She's also the only Cryo character currently available that can create shields, a trait that when paired with her ability to apply Cryo as a status effect easily makes her a top-notch defensive support character. As if this wasn't enough, her elemental burst also heals the party while applying more Cryo to enemies.
Qiqi - Pharmacist
Qiqi is unique in a lot of ways, but perhaps the most distinctive trait about her is that she's a zombie. Resurrected by the Adepti, Qiqi now spends her days working as a pharmacist. When she does get out on the field, though, she's a powerful 5-star Cryo sword user. In combat, Qiqi serves as a great damage dealer, efficient healer, and helps to set up elemental reactions, but her uses extend beyond that. While in the party, items will be marked on the player's minimap, making exploration even easier as well.
Ganyu - Emissary of the Liyue Qixing
Ganyu is an upcoming character expected to be featured in the next promotional banner, and it's said that she has the blood of the Adepti running through her veins. Once added, she'll specialize in the use of the bow weapon, making her the second Cryo bow user alongside Diona. Her elemental skill will allow her to create an ice lotus that taunts enemies and deals AoE Cryo damage, while her burst causes shards of ice to rain down on enemies. Like other Cryo characters, these effects will make elemental reactions easy to set up, but her elemental skill lends towards being a more defensive character overall.
Ayaka - Princess of the Kamisato House
This character was actually playable during Genshin Impact's closed beta tests, but has yet to make a return in the full release of the game. Ayaka is expected to be a 5-star Cryo sword user much like Qiqi, but she likely won't release until March of 2021. From what has been seen of Ayaka, she is looking to be a powerful Primary DPS character, something that the Cryo element is admittedly lacking at the moment, and will even have some abilities to help with exploration.
Rosaria - Nun of the Church of Favonius
Fans just got their first glimpse of Rosaria in the new Albedo event, as she's been tailing both the Traveler and Albedo to make sure they're up to no trouble. It's confirmed that she does have a Cryo Vision, but so far there hasn't been any official statement about her weapon. Leaks indicate that she'll be the first Cryo polearm user, though it's unclear when she'll release. Rosaria is a mysterious character both in terms of personality and abilities, so it's hard to say exactly how she will play in a team.
Cryo Traveler
Finally, it's expected that the Traveler will eventually gain access to Cryo skills after players finally venture into the land of Snezhnaya. According to the Genshin Impact chapter preview, this will be the last region added to the game in its sixth and final story chapter, so it will be a while before this ends up happening. There's also the fact that the Cryo Archon, The Tsaritsa, seems to be an enemy of the traveler's and may not willingly bestow these types of powers.
Genshin Impact is available now on Mobile, PC, and PS4, and later on Switch.