Yep, I prefer "emoji" given the zero plural in Japanese.
I don't think there's a consensus though. For example, Apple uses "emoji" [1], Emojipedia uses "emojis" [2], and the OED includes both [3].
[1]: https://support.apple.com/en-us/HT211808#145
[2]: https://blog.emojipedia.org/first-look-217-new-emojis-in-ios...
[3]: https://www.oed.com/viewdictionaryentry/Entry/389343