Hidden Emojis.

You can rebind the emoji hotkeys here, in the game's folder:
King Arthur's Gold\Base\Entities\Common\Emotes
^ That is the folder dedicated to the emojis.
Complete Steam path:
C:\Program Files (x86)\Steam\SteamApps\common\King Arthur's Gold\Base\Entities\Common\Emotes

EmoteBindings.cfg is the file to edit but keep a clean, non modified version of it in another folder, just to backup.
EmotesCommon.as is the file to look at, in order to get your emoji's "code" (there are 35 emojis, 5 of them are the hidden ones, the cog, the little arrow, the blue and red flag and an invisible one).

Open both of them with an editor (I use notepad++) and think about what you want to change or not.
Get your emoji code in the Emotescommon.as file and enter it in the EmoteBindings.cfg file;
it should look like this: (this is my current configuration)

The numbers from 1 to 9 are obviously your keyboard's keys.
Change them and save the file, then you're ready to start up kag with your brand new emoji configuration!

If you need to see how the emoticons look like ingame:

Spoiler: Here they are

skull
blueflag
note
right
smile
redflag
flex
down
frown
troll
finger
left
mad
archer
sweat
up
laugh
knight
question
thumbsup
wat
builder
disappoint
thumbsdown
derp
ladder
attn
(small arrow) pickup
cry
wall
heart
fire
check
cross
dots
cog

Check out this other thread too

 

The code is 27.