root@ute:~# mysql 
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 9
Server version: 8.0.33-0ubuntu0.22.04.2 (Ubuntu)

mysql> select c,hex(c),upper(c),hex(upper(c)) from t_utf8mb4_0900_ai_ci;

+------+--------+----------+---------------+
| c    | hex(c) | upper(c) | hex(upper(c)) |
+------+--------+----------+---------------+
| ä    | C3A4   | Ä        | C384          |
| ß    | C39F   | ß        | C39F          |
+------+--------+----------+---------------+

2 rows in set (0,00 sec)