The Frequently Used section in the iPhone's Emoji keyboard is a weird place, to say the least. Despite its name, the section features both frequently and recently used emojis, and it may contain emojis you've never even touched. And let's not even talk about its strange way of organizing emojis. If you're sick of seeing weird emojis in there, there is a way to reset what appears in there.
Maybe you used a horrible emoji once and don't ever want to use it again. It could also be that you don't want to leave any evidence of the recent emoji discussion you had with someone via iMessage. Maybe you just want a fresh start. Whatever the case may be, if you're unhappy with the emojis in the Frequently Used section, you can reset it back to Apple's default recommendations for the Emoji keyboard.
There is no way to get rid of the Frequently Used section, at least, not any official means. There could be a jailbreak tweak out there for that, but it's not worth the trouble or security issues that jailbreaking brings up.
Before we get into the how, it's good to point out that by resetting the frequents list for emojis, you're also going to be resetting the keyboard's dictionary settings. That means, predictive text.
When you type a word, Apple may auto-correct it to something else, but you can tap on the change to revert it back to what you really wanted. Every time you reject a predicted word, that custom word is saved to the dictionary so it won't try to auto-correct next time.
So be warned: By resetting the Frequently Used section in the Emoji keyboard, you'll also be resetting your saved custom words, so you'll have to re-teach your keyboard to correctly use words (such as slang or curse words) that it doesn't have in the dictionary. Also, predictive emojis may disappear for a while after resetting the dictionary; continuing to use emojis will bring this feature back.
By following the directions below, you will not be resetting any custom word shortcuts (i.e., Text Replacements), nor will you be affecting any third-party keyboards like Gboard — this only applies to Apple's stock keyboards.
To do so, you must reset the dictionary for Apple's keyboards. Open the Settings app, go into "General," tap on "Reset," and then "Reset Keyboard Dictionary." Enter your passcode, and tap on "Reset Dictionary" to delete all custom words you have saved for the keyboard and return its dictionary back to factory default.
Below, you can see the difference between a keyboard with actual recent and frequently used emojis (left) and one with standard pre-populated emojis (right). Yours will end up looking like the one full of prefilled emoji characters.
Now, whenever you use an emoji, it will appear in the top left spot. When you use another one, it takes its place, pushing the first one down vertically. For each new one, the older ones will keep getting pushed down vertically until they start back up on the next row's top, just to be pushed down again.
However, this is not always the case, and some emojis will stay on the left side while brand new ones appear in the middle. Also, when you use an emoji more than once, it tends to stick to the left side of the section, assuming you'd want quicker access to ones you use more than others.