Is Genshin Impact Crossplay?

Is Genshin Impact crossplay? The new game features both cross-platform play and progression, but there is a caveat to the latter.
Genshin Impact is a new free-to-play action RPG from developer miHoYo. Once players reach Adventure Level 16 they can join other players online. Online play has a few restrictions, like not allowing parties to engage in any main quests. Still, grouping up with friends and slaying monsters is a fun bonus in a game that can be played entirely solo. But what if your friends play on other consoles?
Dear Travelers,
— Paimon (@GenshinImpact) September 28, 2020
Genshin Impact servers are now online across multiple platforms (PS4, iOS, Android, and PC).
Welcome to the world of Teyvat!
Head over to Genshin Impact's Official Site to download the game >>> https://t.co/loCPvhzzMf#GenshinImpact pic.twitter.com/ZjDEBROyeh
Is Genshin Impact Crossplay?
Genshin Impact does feature crossplay. Players on Playstation 4, iOS, Android, PC, and hopefully Nintendo Switch soon, can play seamlessly with one another. The game also features cross-progression. Progress in Genshin Impact is tied to your account and players can log into that same account on any of the consoles the game is available on.
That is, with the exception of PS4. Sony yet again limits the cross-capabilities of a game with Genshin Impact. For now, PS4 players are tied to that console alone. No transferring of your progress from PS4 to another console or vice versa. Perhaps this will be patched in a future update.