I have done a little analysis of and experimentation with Spotify.

experimentation:

I have setup my Spotify account with a Japanese Katakana username, a Chinese hanzi email address and a Korean hangeul password. Native script forms and not romanised forms. It works!!! How cool is that😀

analysis:

Spotify uses google mail. The following is an extract from my terminal session.

苹果电脑 ~: host spotify.com
spotify.com has address 194.132.198.149
spotify.com has address 194.132.197.198
spotify.com has address 194.132.198.198
spotify.com mail is handled by 10 ASPMX4.GOOGLEMAIL.com.
spotify.com mail is handled by 5 ALT1.ASPMX.L.GOOGLE.com.
spotify.com mail is handled by 10 ASPMX5.GOOGLEMAIL.com.
spotify.com mail is handled by 10 ASPMX2.GOOGLEMAIL.com.
spotify.com mail is handled by 1 ASPMX.L.GOOGLE.com.
spotify.com mail is handled by 5 ALT2.ASPMX.L.GOOGLE.com.
spotify.com mail is handled by 10 ASPMX3.GOOGLEMAIL.com.

I also checked with XgenPlus EAI tester https://eai.xgenplus.com/ using address support@spotify.com If you run the test yourself you will see the server advertising SMTPUTF8

So, this explains the Chinese email address part working, as google supports EAI.

André Schappo