Disable Mixmax Emojis
If you have your compose options set to use Mixmax 1.0 compose window, you can automatically convert text to emojis. It is easy to disable this feature in your Mixmax settings. To turn off automatic emojis, go to the Composing section of your Settings in the Mixmax web app. Under Message Options, un-check the box next to Emoji — see the screenshot below:
Note if you are using Mixmax 2.0 as your compose option, you will be able to use Gmail's standard emoji options and will not have the option to disable this feature.