Is it possible to send MMS, Gifs, emojis in sms in Adobe campaign classic.
Let me know if its possible
AC has deprecated MMS option.
Anyway, answer is yes, if your middleware for SMS sending supports MMS sending as well then on AC you can develop new or extend existing SMS channel for mentioned sendouts.
This is not easy therefore should be done by your vendor (assuming that we talking about on-premise solution).
Regarding emojis your SMS connector should have this set (below) in order to send emojis:
This is just AC part. Put some emojis from https://getemoji.com/ in your SMS and send.
If not received properly, then check with middleware team.