As of their 12.2 release they now support long identifiers up to 128 bytes.

https://docs.oracle.com/en/database/oracle/oracle-database/12.2/newft/new-features.html#GUID-ACC0E96C-8D2D-468F-92E0-2013C7F13455

The tricky part could be that depending on the language a character may be multiple bytes.

https://docs.oracle.com/cd/E11882_01/server.112/e10729/ch2charset.htm#NLSPG171

Thanks!